SolidWorks Simulation 2017 Black Book

SolidWorksSimulation2017BlackBook

MattWeber

CAD/CAM/CAEExpert

GauravVermaTechnicalEditor

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DEDICATION

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TrainingandConsultantServicesAtCADCAMCAEWORKS,weprovideeffectiveandaffordableonetooneonline

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individuals, groups, students of colleges/universities, and CAD/CAM/CAE

trainingcenters.Themainfeaturesofthisprogramare:

TrainingasperyourneedHighly experienced Engineers and Technician conduct the classes on the

software applications used in the industries. The methodology adopted to

teach the software is totally practical based, so that the learner can

adapt to the design and development industries in almost no time. The

efforts are to make the training process cost effective and time saving

while you have the comfort of your time and place, thereby relieving you

fromthehasslesoftravelingtotrainingcentersorrearrangingyourtimetable.

SoftwarePackagesonwhichweprovidebasicandadvancedtrainingare:

CAD/CAM/CAE: CATIA, Creo Parametric, Creo Direct, SolidWorks, Autodesk

Inventor, Solid Edge, UG NX, AutoCAD, AutoCAD LT, EdgeCAM, MasterCAM,

SolidCAM, DelCAM, BOBCAM, UG NX Manufacturing, UG Mold Wizard, UG

ProgressiveDie, UG Die Design, SolidWorks Mold, Creo Manufacturing, Creo

Expert Machinist, NX Nastran, Hypermesh, SolidWorks Simulation, Autodesk

SimulationMechanical,CreoSimulate,Gambit,ANSYSandmanyothers.

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soon.

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Civil Engineering: AutoCAD MEP, Revit Structure, Revit Architecture,

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Formoreinformationyoucanmailusat:

[email protected]@cadcamcaeworks.com

PrefaceSolidWorksSimulation2017isanextensiontoSolidWorkspackage.Easy-to-

use CAD-embedded analysis capabilities enable all designers and engineers

to simulate and analyze design performance. You can quickly and easily

employ advanced simulation techniques to optimize performance while you

design,tocutdownoncostlyprototypes,eliminatereworkanddelays,and

saveyoutimeanddevelopmentcosts.

TheSolidWorksSimulation2017BlackBook,iswrittentohelpprofessionalsaswell as learners in performing various tedious jobs of Finite Element

Analysis.Thebookfollowsastepbystepmethodology.Thisbookexplains

the background work running behind your simulation analysis screen. The

bookcoversalmostalltheinformationrequiredbyalearnertomasterthe

SolidWorksSimulation.ThebookstartswithbasicsofFEA,goesthroughall

the simulation tools and ends up with practical examples of analysis.

Chapters on manual FEA ensure the firm understanding of FEA concepts

throughSolidWorksSimulation.Thebookcontainsourspecialsectionsnamed

“Why?”.Wehavegivenreasonsforselectingeveryoptioninanalysisunder

the “Why?” sections. The book explains the Solver selection, iteration

methods like Newton-Raphson method and integration techniques used by

SolidWorks Simulation for functioning. A chapter on Model Preparation is

added in this edition to help you understand the procedures of preparing

modelforanalysis.Someofthesalientfeaturesofthisbookare:

In-DepthexplanationofconceptsEvery new topic of this book starts with the explanation of the basic

concepts.Inthisway,theuserbecomescapableofrelatingthethingswith

realworld.

TopicsCoveredEverychapterstartswithalistoftopicsbeingcoveredinthatchapter.

Inthisway,theusercaneasyfindthetopicofhis/herinteresteasily.

InstructionthroughillustrationThe instructions to perform any action are provided by maximum number of

illustrations so that the user can perform the actions discussed in the

book easily and effectively. There are about 600 illustrations that make

thelearningprocesseffective.

TutorialpointofviewThe book explains the concepts through the tutorial to make the

understandingofusersfirmandlonglasting.Eachchapterofthebookhas

tutorialsthatarerealworldprojects.

“Why?”Thebookexplainsthereasonsforselectingoptionsorsettingaparameters

intutorialsexplainedinthebook.

ProjectFreeprojectsandexercisesareprovidedtostudentsforpracticing.

ForFaculty

If you are a facultymember, then you can ask for video tutorials on any of the topic,exercise,tutorial,orconcept.

FormattingConventionsUsedintheTextAllthekeytermslikenameofbutton,tool,drop-downetc.arekeptbold.

FreeResourcesLink to the resources used in this book are provided to the users via

email. To get the resources, mail us at [email protected] or

[email protected] with your contact information. With your contact

record with us, you will be provided latest updates and informations

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willbeaddressedinspecialthanksareaofourbooks.

AboutAuthorTheauthorofthisbook,MattWeber,haswrittenmanybooksonCAD/CAM/CAE

books. He has written SolidWorks 2017 Black Book as a CAD companion forthis book. When SolidWorks Simulation 2017 Black Book covers details of

simulation, the SolidWorks 2017 Black Book covers all the tools and

techniquesofmodeling.Theauthorhashandonexperienceonalmostallthe

CAD/CAM/CAE packages. Besides that he is a good person in his real life,

helpingnatureforeveryone.Ifyouhaveanyquery/doubtinanyCAD/CAM/CAE

package, then you can directly contact the author by writing at

[email protected]

The technical editor of the book, Gaurav Verma, has written books on CAM

packages. One of his most selling book is Creo Manufacturing 2.0 for

Designer and Machinists. He has also written MasterCAM X7 for SolidWorks

BlackBookandAutoCADElectrical2017BlackBook.

SolidWorks2017BlackBookcanbeusedasSolidWorksCADcompanionwiththisbookforlearningaboutmodelingtools.

TableofContents

SolidWorksSimulation2017

BlackBook

TrainingandConsultantServices

Preface

AboutAuthor

Introductionto

Simulation

Chapter1

Simulation

TypesofAnalysesperformedin

SolidWorksSimulation

StaticAnalysis

DynamicAnalysis

Thermalanalysis

DropTestStudies

FatigueAnalysis

PressureVesselDesignStudy

DesignStudy

FEA

StartingSolidWorksSimulation

OnclickingSimulationAdvisor

OnclickingNewStudy

Basicof

Analyses

Chapter2

StartingAnalysis

ApplyingMaterial

AddingCustomMaterials

DefiningFixtures

FixturesAdvisor

FixedGeometry

Roller/Slider

FixedHinge

ElasticSupport

AdvancedFixtures

ExternalLoadAdvisor

ExternalLoadAdvisor

Force

Torque

Pressure

Gravity

CentrifugalForce

BearingLoad

RemoteLoads/Mass

DistributedMass

Temperature

FlowEffects/ThermalEffects

ConnectionsAdvisor

ConnectionsAdvisor

ContactSets

ComponentContact

ContactVisualizationPlot

Spring

Pin

Bolt

SpotWeld

EdgeWeld

Link

Bearing

RigidConnection

Meshing

RunningAnalysis

ResultsAdvisor

ResultsAdvisor

ModelOnly(NoResults)

NewPlot

ListStress,DisplacementandStrain

ResultForce

PreparingModel

forAnalysis

Chapter3

Introduction

ReferenceGeometry

Plane

PlaneParalleltoScreen

Axis

CoordinateSystem

Point

CenterofMass

Simplify

ExtrudedBoss/BaseTool

RevolvedBoss/BaseTool

ExtrudedCut

Mirror

SplitLinetool

MidSurface

SplitTool

CombineTool

AddingSolidBodies

SubtractingSolidBodies

IntersectTool

Move/CopyBodiesTool

ImportingPart

StaticAnalysis

Chapter4

Linearstaticanalysis

Assumptions

PerformingStaticAnalysis

StartingtheStaticAnalysis

ApplyingMaterial

ApplyingFixtures

ApplyingLoads

Meshingthemodel

RunningtheAnalysis

Results(FactorofSafety)

Optimizingproduct

ShellManager

PerformingStaticAnalysis

UsingStudyAdvisor

StartingtheStaticAnalysis

StaticAnalysisonAssembly

StartingAnalysis

ApplyingMaterialtoPartsofAssembly

SettingGlobalContacts

SettingContactManually

CreatingVirtualWall

CreatingFoundationBoltconnection

ApplyingLoad

Meshing

RunningAnalysis

AdaptiveMeshing

h-AdaptiveMeshing

p-AdaptiveMeshing

SubmodelingStudY

LoadcaseManager

Non-Linear

StaticAnalysis

Chapter5

NonLinearStaticAnalysis

TheoryBehindNon-LinearAnalysis

RoleofTimeinNon-LinearAnalysis

StartingNonlinearStaticAnalysis

ApplyingMaterial

ApplyingFixtures

ApplyingTimeVaryingForce

Runningtheanalysis

SettingPropertiesforNon-linear

StaticAnalysis

PerformingNonlinearStaticanalysis

onanassembly

StartingNon-LinearStaticAnalysis

ApplyingtheMaterial

ApplyingFixtures

ApplyingForces

ApplyingConnections

Runningtheanalysis

PerformingNonlinearStaticanalysison

aringunderapplicationofTorque

StartingNon-LinearStaticAnalysis

ApplyingtheMaterial

ApplyingFixtures

ApplyingForces

Runningtheanalysis

2DSimplification

StartingNon-LinearStaticAnalysiswith2DSimplification

ApplyBoundaryConditions

InterpretingResults

Non-Linear

DynamicAnalysis

Chapter6

NonLinearDynamicAnalysis

PreparingPartandStartingNonlinearDynamicAnalysis

ApplyingMaterial

ApplyingFixtures

ApplyingNoPenetrationContact

SettingInitialConditions

GlobalDamping

RayleighDamping

ApplyingForce

Runningtheanalysis

SettingParametersinNonlinear

DynamicAnalysis

Newton-RaphsonandModifiedN-RMethod

IntegrationMethod

FrequencyAnalysis

Chapter7

Introduction

StartingFrequencyAnalysis

ApplyingMaterial

ApplyingFixtures

ApplyingForces

SettingParametersfortheanalysis

Runningtheanalysis

LinearDynamicAnalysis

Chapter8


Objectivesofadynamicanalysis

Damping

TypesofDynamicAnalysis

ModalTimeHistoryAnalysis

HarmonicAnalysis

RandomVibrationAnalysis

ResponseSpectrumAnalysis

StartingRandomVibrationAnalysis

ApplyingMaterial

ApplyingFixtures

ApplyingForceVibrations

ApplyingGlobalDamping

Runningtheanalysis

ModalTimeHistoryAnalysis

HarmonicAnalysis

ResponseSpectrumAnalysis

ThermalAnalysis

Chapter9

Introduction

ImportanttermsrelatedtoThermalAnalysis

ThermalLoads

Temperature

Convection

HeatPower

HeatFlux

Radiation

ContactSet

ThermalResistanceContact

BondedContact

InsulatedContact

PracticalonSteadyState

ThermalAnalysis

Startingtheanalysis

ApplyingMaterial

Applyingconvectiontothemodel

Applyingheatgeneratedbygascombustionon

theheadofthepiston

RunningtheAnalysis

Switchingfromsteadystateanalysisto

transientthermalanalysis

SpecifyingInitialTemperature

Runningtheanalysis

UsingProbetofindouttemperature

BucklingAnalysis

Chapter10

Introduction

UseofBucklingAnalysis

StartingtheBucklingAnalysis

SettingtheNumberofBucklingModes

ApplyingMaterial

ApplyingFixture

ApplyingtheForce

RunningtheAnalysis

FatigueAnalysis

Chapter11

Introduction

StagesofFailureDuetoFatigue

StartingFatigueAnalysis

InitiatingFatigueAnalysis

ApplyingorEditingS-Ndata

ModifyingtheStaticAnalysisearlierperformed

RunningtheFatigueAnalysis

ChangingPropertiesofFatigueAnalysis

RunningConstantAmplitudeEvents

onthemodel

Drop-Test

Chapter12

Introduction

StartingDropTest

ApplyingMaterial

CreatingMesh

ParametersforDrop

RunningtheAnalysis

PressureVesselDesign

Chapter13

Introduction

ThermalAnalysis1

StaticAnalysis1&2

StartingPressureVesselDesignStudy

SetupforDesignStudy

RunningtheDesignStudy

DesignStudy

StartingDesignStudy

SettingoptionsforDesignStudy

Specifyingparametersthataretobechanged

Specifyingrestrictionsforchanges

SettingGoalforthestudy

RunningtheStudy

FundamentalsofFEA

Chapter14

Introduction

GENERALDESCRIPTIONOFTHEMETHOD

ABRIEFEXPLANATIONOFFEAFOR

ASTRESSANALYSISPROBLEM

FINITEELEMENTMETHODV/SCLASSICALMETHODS

FEMVSFINITEDIFFERENCEMETHOD(FDM)

NEEDFORSTUDYINGFEM

WarningToFeaPackageUsers

GeometricDiscontinuities

DiscontinuityofLoads

DiscontinuityofBoundaryconditions

MaterialDiscontinuity

REFININGMESH

UseOfSymmetry

HIGHERORDERELEMENTSV/S

REFINEDMESH

OptimumprocessofFEAthrough

SolidWorksSimulation

ProjectonAnalysis

Chapter15

Project

StartingSimulation

PerformingtheStaticAnalysis

PerformingtheFrequencyAnalysis

PerformingFatigueStudy

PracticeQuestions

IntroductiontoSimulation

Chapter1

TopicsCovered

Themajortopicscoveredinthischapterare:

•Simulation.

•TypesofAnalysesperformedinSolidWorksSimulation.

•FEA

•UserInterfaceofSolidWorksSimulation.

SIMULATIONSimulation is the study of effects caused on an object due to real-world

loadingconditions.ComputerSimulationisatypeofsimulationwhichuses

CADmodelstorepresentrealobjectsanditappliesvariousloadconditions

onthemodeltostudythereal-worldeffects.SolidWorksSimulationisone

oftheComputerSimulationprogramsavailableinthemarket.InSolidWorks

Simulation, we apply loads on a constrained model under predefined

environmentalconditions and check the result(visually and/or in the form

oftabulardata).ThetypesofanalysesthatcanbeperformedinSolidWorks

aregivennext.

TYPESOFANALYSESPERFORMEDINSOLIDWORKSSIMULATION

SolidWorksSimulation performs almost all the analyses that are generally

performedinIndustries.Theseanalysesandtheirusearegivennext.

StaticAnalysisThis is the most common type of analysis we perform. In this analysis,

loadsareappliedtoabodyduetowhichthebodydeformsandtheeffects

oftheloadsaretransmittedthroughoutthebody.Toabsorbtheeffectof

loads,thebodygeneratesinternalforcesandreactionsatthesupportsto

balance the applied external loads. These internal forces and reactions

cause stress and strain in the body. Static analysis refers to the

calculation of displacements, strains, and stresses under the effect of

externalloads,basedonsomeassumptions.Theassumptionsareasfollows.

• All loads are applied slowly and gradually until they reach their full

magnitudes. After reaching their full magnitudes, load will remain

constant(i.e.loadwillnotvaryagainsttime).

• Linearity assumption: The relationship between loads and resulting

responsesislinear.Forexample,ifyoudoublethemagnitudeofloads,

theresponseofthemodel(displacements,strainsandstresses)willalso

double.Youcanmakelinearityassumptionif:

1. All materials in the model comply with Hooke’s Law that is stress is

directlyproportionaltostrain.

2. The induced displacements are small enough to ignore the change is

stiffnesscausedbyloading.

3.Boundaryconditionsdonotvaryduringtheapplicationofloads.Loads

mustbeconstantinmagnitude,directionanddistribution.Theyshouldnot

changewhilethemodelisdeforming.

Iftheaboveassumptionsarevalidforyouranalysis,thenyoucanperform

LinearStaticAnalysis.Forexample,acantileverbeamfixedatoneendand

forceappliedonotherend;refertoFigure-1.

Figure-1.Linearstaticanalysisexample

Iftheaboveassumptionsarenotvalid,thenyouneedtoperformtheNon-Linear Static analysis. For example, an object attached with a spring beingappliedunderforces;refertoFigure-2.

Figure-2.Non-linearstaticanalysisexample

DynamicAnalysisIn general, we have to perform dynamic analysis on a structure when the

load applied to it varies with time. The most common case of dynamic

analysis is the evaluation of responses of a building due to earthquake

acceleration at its base. Every structure has a tendency to vibrate at

certainfrequencies,callednaturalfrequencies.Eachnaturalfrequencyis

associatedwithacertainshape,calledmodeshapethatthemodeltendsto

assumewhenvibratingatthatfrequency.Whenastructureisexcitedbya

dynamic load that coincides with one of its natural frequencies, the

structure undergoes large displacements. This phenomenon is known as

‘resonance’. Damping prevents the response of the structures to resonant

loads. In reality, a continuous model has an infinite number of natural

frequencies.However,afiniteelementmodelhasafinitenumberofnatural

frequenciesthatisequaltothenumberofdegreesoffreedomconsideredin

themodel.Thefirstfewmodesofamodel(thosewiththelowestnatural

frequencies), are normally important. The natural frequencies and

corresponding mode shapes depend on the geometry of the structure, its

material properties, as well as its support conditions and static loads.

The computation of natural frequencies and mode shapes is known as modal

analysis. When building the geometry of a model, you usually create it

basedontheoriginal(undeformed)shapeofthemodel.Someloading,likea

structure’s self-weight, is always present and can cause considerable

changesin the structure’s original geometry. These geometric changes may

have, in some cases, significant impact on the structure’s modal

properties.Inmanycases,thiseffectcanbeignoredbecausetheinduced

deflectionsaresmall.

The following few topics – Random Vibration, Response Spectrum analysis,

Time History analysis, Transient vibration analysis and Vibration modal

analysisareextensionsofdynamicanalysis.

RandomVibrationEngineersusethistypeofanalysistofindouthowadeviceorstructure

respondstosteadyshakingofthekindyouwouldfeelridinginatruck,

railcar,rocket(whenthemotorison),andsoon.Also,thingsthatare

ridinginthevehicle,suchason-boardelectronicsorcargoofanykind,

may need Random Vibration Analysis. The vibration generated in vehicles

from the motors, road conditions, etc. is a combination of a great many

frequencies from a variety of sources and has a certain “random” nature.

Random Vibration Analysis is used by mechanical engineers who design

variouskindsoftransportationequipment.

ResponseSpectrumAnalysisEngineersusethistypeofanalysistofindouthowadeviceorstructure

responds to sudden forces or shocks. It is assumed that these shocks or

forcesoccuratboundarypoints,whicharenormallyfixed.Anexamplewould

beabuilding,damornuclearreactorwhenanearthquakestrikes.Duringan

earthquake, violent shaking occurs. This shaking transmits into the

structure or device at the points where they are attached to the ground

(boundarypoints).

Mechanical engineers who design components for nuclear power plants must

use response spectrum analysis as well. Such components might include

nuclear reactor parts, pumps, valves, piping, condensers, etc. When an

engineer uses response spectrum analysis, he is looking for the maximum

stressesor acceleration, velocity and displacements that occur after the

shock.Theseinturnleadtomaximumstresses.

TimeHistoryAnalysisThis analysis plots response (displacements, velocities, accelerations,

internal forces etc.) of the structure against time due to dynamic

excitationappliedonthestructure.

TransientVibrationAnalysisWhenyoustrikeaguitarstringoratuningfork,itgoesfromastateof

inactivityintoavibrationtomakeamusicaltone.Thistoneseemsloudest

atfirst,thengraduallydiesout.Conditionsarechangingfromthefirst

moment the note is struck. When an electric motor is started up, it

eventuallyreachesasteadystateofoperation.Buttogetthere,itstarts

from zero RPM and passes through an infinite number of speeds until it

attainstheoperatingspeed.Everytimeyourevthemotorinyourcar,you

are creating transient vibration. When things vibrate, internal stresses

are created by the vibration. These stresses can be devastating if

resonance occurs between a device producing vibration and a structure

respondingto.Abridgemayvibrateinthewindorwhencarsandtrucksgo

across it. Very complex vibration patterns can occur. Because things are

constantlychanging,engineersmustknowwhatthefrequenciesandstresses

are at all moments in time. Sometimes transient vibrations are extremely

violentandshort-lived.Imagineatorpedostrikingthesideofashipand

exploding, or a car slamming into a concrete abutment or dropping a

coffeepot on a hard floor. Such vibrations are called “shock, “ which is

justwhatyouwouldimagine.Inreallife,shockisrarelyagoodthingand

almost always unplanned. But shocks occur anyhow. Because of vibration,

shock is always more devastating than if the same force were applied

gradually.

VibrationAnalysis(ModalAnalysis)Byits very nature, vibration involves repetitive motion. Each occurrence

ofacompletemotionsequenceiscalleda“cycle.”Frequencyisdefinedas

so many cycles in a given time period. “Cycles per seconds” or “Hertz”.

Individual parts have what engineers call “natural” frequencies. For

example,aviolinstringatacertaintensionwillvibrateonlyataset

numberoffrequencies,whichiswhyyoucanproducespecificmusicaltones.

There is a base frequency in which the entire string is going back and

forthinasimplebowshape.

Harmonicsandovertonesoccurbecauseindividualsectionsofthestringcan

vibrateindependentlywithinthelargervibration.Thesevariousshapesare

called “modes”. The base frequency is said to vibrate in the first mode,

andsoonuptheladder.Eachmodeshapewillhaveanassociatedfrequency.

Higher mode shapes have higher frequencies. The most disastrous kinds of

consequencesoccurwhenapower-drivendevicesuchasamotorforexample,

produces a frequency at which an attached structure naturally vibrates.

This event is called “resonance.” If sufficient power is applied, the

attached structure will be destroyed. Note that ancient armies, which

normallymarched“instep,”weretakenoutofstepwhencrossingbridges.

Shouldthebeatofthemarchingfeetalignwithanaturalfrequencyofthe

bridge, it could fall down. Engineers must design so that resonance does

notoccurduringregularoperationofmachines.Thisisamajorpurposeof

Modal Analysis. Ideally, the first mode has a frequency higher than any

potential driving frequency. Frequently, resonance cannot be avoided,

especiallyforshortperiodsoftime.Forexample,whenamotorcomesupto

speed it produces a variety of frequencies. So it may pass through a

resonantfrequency.

BucklingAnalysisIfyoupressdownonanemptysoftdrinkcanwithyourhand,notmuchwill

seemtohappen.Ifyouputthecanonthefloorandgraduallyincreasethe

forcebysteppingdownonitwithyourfoot,atsomepointitwillsuddenly

squash.Thissuddenscrunchingisknownas“buckling.”

Modelswiththinpartstendtobuckleunderaxialloading.Bucklingcanbe

defined as the sudden deformation, which occurs when the stored

membrane(axial)energyisconvertedintobendingenergywithnochangein

the externally applied loads. Mathematically, when buckling occurs, the

totalstiffnessmatrixbecomessingular.

In the normal use of most products, buckling can be catastrophic if it

occurs.Thefailureisnotonebecauseofstressbutgeometricstability.

Oncethegeometryofthepartstartstodeform,itcannolongersupport

even a fraction of the force initially applied. The worst part about

buckling for engineers is that buckling usually occurs at relatively low

stressvaluesforwhatthematerialcanwithstand.Sotheyhavetomakea

separatechecktoseeifaproductorpartthereofisokaywithrespectto

buckling.

Slender structures and structures with slender parts loaded in the axial

direction buckle under relatively small axial loads. Such structures may

fail in buckling while their stresses are far below critical levels. For

suchstructures,thebucklingloadbecomesacriticaldesignfactor.Stocky

structures, on the other hand, require large loads to buckle, therefore

bucklinganalysisisusuallynotrequired.

Buckling almost always involves compression; refer to Figure-3. In

mechanicalengineering,designsinvolvingthinpartsinflexiblestructures

like airplanes and automobiles are susceptible to buckling. Even though

stress can be very low, buckling of local areas can cause the whole

structuretocollapsebyarapidseriesof‘propagatingbuckling’.Buckling

analysis calculates the smallest (critical) loading required buckling a

model. Buckling loads are associated with buckling modes. Designers are

usually interested in the lowest mode because it is associated with the

lowest critical load. When buckling is the critical design factor,

calculatingmultiplebucklingmodeshelpsinlocatingtheweakareasofthe

model. This may prevent the occurrence of lower buckling modes by simple

modifications.

Figure-3.Bucklingexample

ThermalanalysisThere are three mechanisms of heat transfer. These mechanisms are

Conduction, Convection and Radiation. Thermal analysis calculates the

temperaturedistributioninabodyduetosomeorallofthesemechanisms.

Inallthreemechanisms,heatflowsfromahigher-temperaturemediumtoa

lowertemperatureone.Heattransferbyconductionandconvectionrequires

thepresenceofaninterveningmediumwhileheattransferbyradiationdoes

not.

Therearetwomodesofheattransferanalysis.

SteadyStateThermalAnalysisInthistypeofanalysis,weareonlyinterestedinthethermalconditions

ofthebodywhenitreachesthermalequilibrium,butwearenotinterested

inthetimeittakestoreachthisstatus.Thetemperatureofeachpointin

the model will remain unchanged until a change occurs in the system. At

equilibrium,thethermalenergyenteringthesystemisequaltothethermal

energyleavingit.Generally,theonlymaterialpropertythatisneededfor

steadystateanalysisisthethermalconductivity.

TransientThermalAnalysisInthistypeofanalysis,weareinterestedinknowingthethermalstatus

of the model at different instances of time. A thermos designer, for

example,knowsthatthetemperatureofthefluidinsidewilleventuallybe

equal to the room temperature(steady state), but he is interested in

findingoutthetemperatureofthefluidasafunctionoftime.Inaddition

to the thermal conductivity, we also need to specify density, specific

heat, initial temperature profile, and the period of time for which

solutionsaredesired.

Tillthispoint,wehavelearnedthebasicsofvariousanalysesthatcanbe

performedinSolidWorks.Now,wewilllearnaboutthestudiesthatcanbe

performedinSolidWorks.

DROPTESTSTUDIESDropteststudiessimulatetheeffectofdroppingapartoranassemblyon

arigidorflexiblefloor.Toperformthisstudythefloorisconsideredas

planar and flat. The forces that are considered automatically for this

studyaregravityandimpactreaction.

FATIGUEANALYSISThefatigueismoreoverastudythenanalysis.Butitisgenerallynamed

as analysis. This analysis is used to check the effect of continuous

loadingandunloadingofforcesonabody.Thebaseelementforperforming

fatigueanalysisareresultsofstatic,nonlinear,ortimehistorylinear

dynamicstudies.

PRESSUREVESSELDESIGNSTUDYPressure Vessel Design study allows you combine the results of static

studies with the desired factors and interpret the results. The Pressure

Vessel Design study combines the results of the static studies

algebraicallyusingalinearcombinationorthesquarerootofthesumof

thesquares.

DESIGNSTUDYDesignStudyisusedtoperformanoptimizationofdesign.UsingtheDesign

Studyyoucan:

•Definemultiplevariablesusingsimulationparameters,ordrivingglobal

variables.

•Definemultipleconstraints.

•Definemultiplegoalsusingsensors.

•Analyzemodelswithoutsimulationresults.Forexample,youcanminimize

themassofanassemblywiththevariables,densityandmodeldimensions,

theconstraint,andvolume.

•Evaluatedesignchoicesbydefiningaparameterthatsetsbodiestouse

differentmaterialsasavariable.

Till this point, you have become familiar with the analyses that can be

performed by using SolidWorks. But, do you know how the software analyze

theproblems.TheanswerisFEA.

FEAFEA,FiniteElementAnalysis,isamathematicalsystemusedtosolvereal-

worldengineeringproblemsbysimplifyingthem.InFEAbySolidWorks,the

modelisbrokenintosmallelementsandnodes.Then,distributedforcesare

applied on each element and node. The cumulative result of forces is

calculatedanddisplayedinresults.Theelementsinwhichamodelcanbe

brokenintoaregiveninFigure-4,Figure-5,andFigure-6.

Figure-4.Finiteelementslist1



We will be now use the information discussed above in SolidWorks

Simulation.TheprocessofstartingSolidWorksSimulationisgivennext.

STARTINGSOLIDWORKSSIMULATIONBefore you try to start SolidWorks Simulation, make sure that you have

installeditwithSolidWorksandyouappliedtheserialkeyforitduring

installation.Then,followthestepsgivennext.

• Start SolidWorks and open the model for which you want to perform the

analyses.

•ClickontheSolidWorksAdd-InstabandselecttheSolidWorksSimulationbutton;refertoFigure-7.

•Onclickingthisbutton,SimulationtabwillbeaddedintheRibbon.

•ClickontheSimulationtab,theNewStudydrop-downwillbedisplayedintheRibbon.

There are two buttons available in this drop-down;SimulationAdvisor andNewStudy.WewillstartwithSimulationAdvisorasitisgoodfornovicestothesoftware.

Figure-7.SolidWorkssimulationbutton

OnclickingSimulationAdvisor•ClickontheSimulationAdvisorbuttonfromthedrop-down.TheSimulationAdvisorpanewilldisplayintherightoftheSolidWorkswindow;refertoFigure-8.

Figure-8.Simulationadvisorpane

•ReadthetextintheAdvisorandperformtheactionsaccordingly.Thisis

aguidedprocesssoitisrecommendedtoperformsometricksonsoftware

byyourself.Wewilllearnmoreabouttheadvisorlaterinthebook.

OnclickingNewStudy• Click on the New Study button from the drop-down. The StudyPropertyManagerwilldisplay;refertoFigure-9.

Figure-9.StudyPropertyManager

ThebuttonsavailableintheTyperolloutofthePropertyManagerrefertodifferenttypeofanalyses.

Wewilldiscusstheseanalysesonebyoneintheupcomingchapters.

BasicofAnalyses

Chapter2

TopicsCovered


•StartingAnalysis

•ApplyingMaterial

•DefiningFixtures

•Applyingloads

•DefiningConnections

•SimulatingAnalysis

•Interpretingresults

STARTINGANALYSISTherearetwomethodstostartananalysisinSolidWorksSimulation;using

StudyAdvisorandusingNewStudybutton.WewillusetheNewStudybuttonthroughout the book. Although we will give short notes for using StudyAdvisor to perform the analyses. The steps to start static analysis aregivennext.

• Click on theNewStudy button from the Study Advisor drop-down in theSimulationtabofRibbon.TheStudyPropertyManagerwilldisplay.

•ClickontheStaticbuttonfromthePropertyManagerandspecifythenameofanalysisasdesiredintheNamerollout.

• Click on theOK button from the PropertyManager. The interface willdisplayasshowninFigure-1.

Figure-1.Staticanalysisinterface

Thefirststepforthisanalysisistoapplymaterialonthemodel.

APPLYINGMATERIALMaterial is a key input for any analysis. The result of analysis is

directly related to material of the object. There are few properties of

materiallike,ultimatestrength,hardness,andyoung’smoduluswhichplay

importantroleinsuccess/failureoftheobjectunderspecifiedload.Also,

materialdeterminestheapplicationofobjectinrealworld.Forexample,

wedonotuseglasstomakepistonsinengine.Thestepstoapplymaterial

onobjectaregivennext.

•ClickontheApplyMaterialbuttonfromtheSimulationtabintheRibbon.TheMaterialdialogboxwilldisplayasshowninFigure-2.

Figure-2.Materialdialogbox

Alibraryofstandardmaterialsisavailableinthisboxforselection.

• Select the desired material from left pane of the box. The related

parameterswillbedisplayedattheright.

•ClickontheApplybuttontoapplythematerial.

•ClickontheClosebuttontoclosethebox.

Although,wehaveabiglibraryofstandardmaterialsavailablebutstill

there is always a need to custom material. Now, we will discuss about

addingcustommaterialsinlibrary.

AddingCustomMaterialsBig researches are going on to enhance the properties of engineering

materialstomakethemlighterandstronger.Duringyourjob,youmaycome

across a material whose properties are not available in the library. In

suchacase,followthestepsgivennexttocreatecustommaterial.

• Right-click on theMaterial option from theFeatureManagerDesignTreeand select the Edit Material option from the short-cut menu displayed;

refertoFigure-3.TheMaterialdialogboxwillbedisplayedasshowninFigure-2earlier.

Figure-3.EditMaterialoption

• Right-click on the material whose properties are close to the material

you want to create and select theCopy option from the shortcut menudisplayed;refertoFigure-4.

Figure-4.Copyoptionformaterial

•Now,movetothebottomofmateriallistandexpandtheCustomMaterialcategory;refertoFigure-5.

Figure-5.CustomMaterialcategory

•Right-clickontheCustomMaterialscategoryandselecttheNewCategoryoptiontoaddanewsub-categoryinit.Specifythedesiredname;referto

Figure-6.

•Right-clickonthenewsub-categoryandselectthePasteoptionfromtheshortcutmenu;refertoFigure-7.Thecopiedmaterialwillbeaddedinthe

sub-categorybutwiththeedit-ablefeatures.Notethatyoucanstartwith

a completely new material by using theNewMaterial option in place ofPasteoption.

Figure-6.Newcategoryadded

Figure-7.Pasteoptionformaterials

•Clickontheaddedmaterial,theoptionsrelatedtothematerialswillbe

displayedontherightindialogbox;refertoFigure-8.

•Clickintheeditboxesandspecifythedesiredvalues.

• Click on theSave button to save the parameters and then click on theClose button. Now, you can use this custom material like standard

materials.

Figure-8.Detailsofcustommaterial

DEFININGFIXTURESTo perform any analysis, it is important to fix the object by some

constrainssothattheeffectofappliedforcescanbechecked.Ifyoudo

notapplyfixturesthentheobjectwillbefreetomoveinthedirectionof

forces applied and no stress or strain will be induced in it. There are

variousoptionsforconstraintheobject.Alltheseoptionsareexplained

next.

FixturesAdvisorThisbuttonisusedtocreatefixturesinaguidedway.Aninteractivetask

paneisusedtoapplyfixturesonthebasisofyourresponses.Thestepsto

usethistoolaregivennext.

•ClickontheFixturesAdvisorbuttonfromtheFixturesAdvisordrop-downinthe Ribbon. The Simulation Advisor will display in the right of the

window;refertoFigure-9.

• Click on theAdd a fixture option from the SimulationAdvisor pane. TheFixturePropertyManagerwillbedisplayed;refertoFigure-10.

Figure-9.SimulationAdvisor

Figure-10.FixturePropertyManager

Note that the options displayed in the PropertyManager can be directlychosenfromtheFixtureAdvisordrop-downintheRibbon;refertoFigure-11.Various options in the PropertyManager and the drop-down are discussed

next.

Figure-11.FixturesAdvisordrop-down

FixedGeometryThisisthemostcommonlyusedfixturetype.Usingthisfixturetype,you

can fix the face, edge or point of the object. To apply this fixture,

followthestepsgivennext.

•ClickontheFixedGeometry button from theFixturesAdvisor drop-down.TheFixturePropertyManagerwilldisplayasshowninFigure-10.

• Make sure that the Fixed Geometry button is selected in the Standard(FixedGeometry)rollout.

•Selectthefacethatyouwanttobefixed;refertoFigure-12.

Figure-12.Faceselectedforfixing

•ClickOKbuttontodefinethefixture.

YoucanalsosplitafacebeforeclickingOKtopreciselydefinethefixed

area.Thestepstodosoaregivennext.

• Click on the Split tab from the Fixture PropertyManager. The

PropertyManagerwilldisplayasshowninFigure-13.

•ClickontheCreateSketchbuttonfromthePropertyManager.Youareaskedtoselectaplane/faceforsketchingifnotselectedearlierforcreating

fixture.

•Selectthedesiredplanetosketchthesplittingline.

• Create the splitting line by using theLine tool; refer to Figure-15.Notethatyoucancreateanydesiredshapebyusingthetoolsactivein

theRibbon;refertoFigure-14.

Figure-13.FixturePropertyManagerwithsplittab

Figure-14.Sketchcreatedforsplitting

•ClickontheExitSketchbuttondisplayedinSplitboxinviewport.Youareaskedtoselectaface.

•Selectthefacesthatyouwanttosplitbytheprojectionofdrawnsketch

line;refertoFigure-16.

Figure-15.Splittinglinedrawn

Figure-16.Facesselectedforsplitting

• Click on the Create Split button from the Selection rollout of the

PropertyManager.Theselectedfaceswillgetsplit;refertoFigure-17.

Figure-17.Facesaftersplitting

•ClickontheTypetabofthePropertyManagertodisplayoptionsrelatedtofixture.

• Click on the faces that you want to fix and remove unwanted faces by

right-clicking and then selecting the Delete option from the shortcut

menu;refertoFigure-18.

Figure-18.Splittedfacesselectedforfixing

•ClickonOKbuttonfromthePropertyManagertofixthefaces.

Where should we use the FixedGeometry fixture? The answer is: we usethisconstraintwhereweknowthattheselectedfaceislyingonahardsurfaceandit cannot move due to action of any applied forces. A live example can be a

buildingfixedtoearthbyitsbase.Weexpectthebuildingnottomoveif

loadincreasesduetosomeunexpectedguests.

Figure-19.FixturePropertyManagerforrollersliderfixture

Roller/SliderThisoptionisusedtofixafaceinsuchawaythatitcanslide/rollin

itsplanebutcannotmoveperpendiculartotheplane.Thestepstofixa

facebyusingthisoptionaregivennext.

•ClickontheRoller/SliderbuttonfromtheFixturesAdvisordrop-down.TheFixture PropertyManager will be displayed similar to the one discussedearlierbutwiththeRoller/Sliderbuttonselected;refertoFigure-19.

•Selectthefacethatyouwanttoallowforslidingorrolling.Referto

Figure-20.

•ClickontheOKbuttonfromthePropertyManagertoapplythefixture.

Figure-20.Sliderfaceselection

Herethequestioncomes,whereshouldweusetheRoller/Sliderfixture?Theansweris:weusethisconstraintwhereobjectcanrollorslideonasurfacebutcannotmovenormaltoit.AliveexamplecanbeTyreofanautomobilewhichrolls on the road and it is expected not to move up towards the sky or

down.

FixedHingeThisoptionisusedtofixacylindricalfaceinsuchawaythattheface

acttobehinged.Thestepstoapplyhingefixturearegivennext.

• Click on the Fixed Hinge tool from the Fixtures Advisor drop-down. TheFixture PropertyManager will be displayed with the Fixed Hinge button

selected;refertoFigure-21.

•Selectacylindricalfacethatyouwanttofixashinge;refertoFigure-

22.

•ClickontheOKbuttontoapplythefixture.

Figure-21.FixturePropertyManagerforfixedhingefixture

Figure-22.Faceselectedforhinge

WhereshouldweusetheFixedHingefixture?Theansweris:weusethisconstraintwhereobjectcanrevolvearound itsaxis.Aliveexamplecanbecarhood(alsocalledcarbonnetinsomeregionsofworld).

ElasticSupport

Thisoptionisusedtoinsertanelasticsupportbetweenfloorandobject.

Thistypeoffixtureisgenerallyappliedtorubberorplasticparts.The

stepstoapplythisfixturearegivennext.

• Click on theElastic Support button from theFixtures Advisor drop-down.TheConnectorPropertyManagerwilldisplayasshowninFigure-23.

Figure-23.ConnectorsPropertyManager

• Select the face that you want to make as elastic support; refer to

Figure-24.

•Clickinthedrop-downofStiffnessrollouttospecifythetypeofunitstobeusedtospecifythevalueofstiffness.

• Select the desired option from the SI, English (IPS), and Metric (G)option.

• Click in the Normal edit box and specify the stiffness of elastic

supportinnormaldirectiontotheselectedface.

• Click in theShear edit box and specify the value of stiffness in thelateraldirection(alsoknownasstiffnessinsheardirection).

• You can specify the total stiffness in normal and shear direction by

selecting theTotal radio button in place ofDistributed in the Stiffnessrollout.

•ClickontheOKbuttontodefinethefixture.

Figure-24.Selectingfaceforelasticsupport

Where should we use the Elastic Support fixture? The answer is: we usethisconstraintwhereobject isplacedor fastenedona soft surface likewoodorrubber.Aliveexamplecanbeanobjectplacedonwood,rubberoranyspringbase.Ihopeyouhaveseenkidsjumpingonthebed,theyreboundbecauseof

elasticpropertyofmattressonbed.

Figure-25.Advancedfixtureoptions

AdvancedFixturesThere are some advanced fixtures available in SolidWorks Simulation for

constraining the objects. To apply these fixtures follow the steps given

next.

•ClickontheAdvancedFixturesbuttonfromtheFixturesAdvisordrop-downintheRibbon.TheFixturePropertyManagerwillbedisplayedasshowninFigure-25.

TheoptionsavailableinthisPropertyManagerarediscussednext.

SymmetryTheSymmetrybuttonisusedtosimplifythegeometryofthemodelbeinganalyzed. This option gives us freedom to analyze half of the body and

hence reducing size of the problem. Based on this result the effect on

whole body can be analyzed. This option is not recommended if you are

performingbucklingorfrequencystudies.Thestepstousethisoptionare

givennext.

•ClickontheSymmetrybuttonfromthePropertyManager.Youareaskedtoselectafacetodefinesymmetry.

•Selectthefacethatissymmetrichalforquarterofthemainpart.Refer

toFigure-26.Notethatyoucancreateanalyzeapartusingquarterofit

ifthepartissymmetricandotherloadingconditionsaresameforfull

part.Tousequarterpart,youwillberequiredtoselecttwofacesfor

definingsymmetry;refertoFigure-27.

Figure-26.Symmetricfixtureapplication

Figure-27.Partsymmetryusingquartersection


Where should we use the Symmetry fixture? The answer is: we use thisconstraintwhereobjectissymmetricaboutaplaneorface.Theliveexamplecanbeaflattablewhichcanbedividedintotwoorfoursamesections.

CyclicSymmetryThisbuttonisusedtocreatesymmetryforcircularobjects.Notethatthe

parts that can be used for circular symmetry are generally created by

Revolve tool and are having an axis for symmetry. The steps to use thisoptionaregivennext.

•ClickontheCyclic Symmetry button from thePropertyManager. You areaskedtoselectstartingfaceforcircularsymmetry;refertoFigure-28.

Selectthedesiredface.

Figure-28.Faceselectionforcyclicsymmetry

•ClickinthenextboxinPropertyManagerandselecttheendingfaceforcircular symmetry. Similarly, click in the axis selection box in

PropertyManager and then select the axis about which the part is

symmetric. Preview of symmetry will be displayed as shown in Figure-29.

Note that the axis should have been created byAxis tool inReferenceGeometrydrop-downintheAnalysisPreparationCommandManager.

Figure-29.Previewofsymmetryfixture

•ClickontheOKbuttontoapplythecircularsymmetryfixture.

Where shouldweuse theCyclicSymmetry fixture?Theansweris:weusethisconstraintwhereobjectcanbecreatedbysymmetricblockssharingthesameaxis.Aliveexamplecanbealloywheels.

UseReferenceGeometryThis button is used to fix the linear/rotational degree of freedom of a

body.Therotationalconstraintcanbeappliedonshellsandbeamsonly.To

applythisfixture,followthestepsgivennext.

Figure-30.FixturePropertyManagerwithUseReferenceGeometrybuttonselected

• Click on the Use Reference Geometry button from the FixturePropertyManager. The options in the PropertyManager will display as

showninFigure-30.

•Selectafaceonwhichyouwanttoapplythefixture.Notethatyoucan

alsoselectanedgeorvertexforfixture.

•ClickinthenextselectionboxinPropertyManagerandselectanedgeorfacetodefinethedirectionreference.

•ClickintheUnitdrop-downintheTranslationsdrop-downandselectthedesiredunittype.

• Click on the desired direction button from rollout and specify the

distancelimittowhichtheselectedfacecanmove/rotate.

•Thedirectionsforwhichbuttonsarenotselectedarefree.

OnFlatFacesThisbuttonisusedtofixaflatfaceinthedesireddirection.Youcan

also specify the distance limit in specific directions by using this

option.Thestepstousethisbuttonaregivennext.

•ClickontheOnFlatFacesbuttonfromtheFixturePropertyManager. ThePropertyManagerwilldisplayasshowninFigure-31.

•Selectthefacefromthemodelthatyouwanttofix.

• Click on the button of direction in which you want to specify the

distancelimit.

•Specifythedesireddistanceintheeditbox.Ifyouwanttofixthebody

inadirectionthenspecifythevalueas0.•Youcanclickonmorethanonebuttontoconstrainmoredirections;refer

toFigure-32.

Figure-31.FixturePropertyManagerwithOnFlatFacesbutton

Figure-32.Previewofonflatfacesfixture

•ClickontheOKbuttonfromthePropertyManagertoapplythefixture.Figure-33.FixturePropertyManageronselectingOnCylindricalFacesbutton

OnCylindricalFacesThis button is used to fix a cylindrical face in the desired direction.

ThisoptionworksinthesamewayasOnFlatFacesbuttonworks.Thestepstousethisoptionaregivennext.

• Click on the On Cylindrical Faces button. The options in the

PropertyManagerwilldisplayasshowninFigure-33.•Selectthecylindricalfaceofthemodelandselectthebuttonsforthe

directionsforwhichyouwanttoconstrainthebodymovement.

• Specify the distance/rotation limit for the body for the selected

directionbuttons.RefertoFigure-34.

Figure-34.Previewofoncylindricalfacesfixture

OnSphericalFacesThisbuttonisusedtofixasphericalfaceinthedesireddirections.This

option works in the same way as On Cylindrical Faces option. The only

differenceisthatyouneedtoselectsphericalfaceforOnSphericalFacesoption.Restoftheprocedureissame.RefertoFigure-35.

Now,youknowallthetypeoffixturesavailableinSolidWorksSimulation.

Thenextstepistoapplytheforcesontheobjects.

Figure-35.Previewofonsphericalfacesfixture

EXTERNALLOADADVISORTheoptionsinthisdrop-downareusedtoapplyvarioustypesofforceson

thebody.Theoptionsinthedrop-downarediscussednext.

ExternalLoadAdvisorThisoptionisusedtodisplaytheSimulationAdvisorwiththepagerelatedtoforce.Thestepstousethisoptionaregivennext.

•ClickontheExternalLoadsAdvisoroptionfromtheExternalLoadAdvisordrop-downintheSimulationtaboftheRibbon.TheSimulationAdvisorwilldisplayintherightofthescreenasshowninFigure-36.

•ClickontheAdda loadlinkbuttonfromtheadvisortoapplytheload.The options related to forces will displayed in the Force/TorquePropertyManager; refer to Figure-37. You can display the same

PropertyManagerbyusingtheForcetoolfromtheExternalLoadsAdvisordrop-downintheRibbon.Themethodisdiscussednext.

ForceThis is the mostly used option in SolidWorks Simulation for applying

forces.Toapplytheforces,followthestepsgivennext.

•ClickontheForceoptionfromtheExternalLoadsAdvisordrop-downintheRibbon. The Force/Torque PropertyManager will display as shown in

Figure-37.

Figure-36.SimulationAdvisorwithoptionsforload

Figure-37.ForceTorquePropertyManager

•Selectthefaceonwhichyouwanttoapplytheforce.

•Tochangethedirectionofforce,selecttheSelecteddirectionradiobuttonfrom the PropertyManager. You will be asked to select reference for

directionviaapinkselectionbox;refertoFigure-38.

• Click in this selection box and select a reference to specify the

directionofforce;refertoFigure-39.Notethatyouneedtoselectthe

force vector buttons from the Force rollout in the PropertyManager toapplyforcesindesiredcomponentofselecteddirection.

Figure-38.Forceinselecteddirection

Figure-39.Forceappliedinselecteddirection

• If you have selectedNormal radio button in thePropertyManager thenclickintheForceValueeditboxandspecifythedesiredvalue.

•Youcanchangetheunittypebyselectingdesiredoptionfromthedrop-

downintheForce/Torquerollout.• If you have non uniform distribution of force and have an equation of

distribution then click on the check box of Nonuniform Distributionrollout. The options related to Non-uniform distribution of force will

display;refertoFigure-40.

Figure-40.Nonuniformforcedistribution

• There are three coordinate systems to define the equation, Cartesian

CoordinateSystem,CylindricalCoordinateSystem,andSphericalCoordinate

System.SelectthedesiredbuttonfromtheTypeofCoordinateSystemarea

ofrollout;refertoFigure-41.

Figure-41.Coordinatesystemselection

• Click on the Edit Equation button from the rollout. The Edit Equationdialogboxwillbedisplayedaspertheselectedcoordinatesystem;refer

toFigure-42.

Figure-42.EditEquationdialogbox

SetthedesiredequationofforceintheeditboxinEditEquationdialog

box.Anexampleofsuchequationisgivennext:

F(X,Y,Z)=A+B*”X”+C*”Y”+D*”X”*”Y”+E*”X”^2+F*”Y”^2+G*”Z”^2

•Inthisequation,youneedtoenterthenumericalvaluesofA,B,C,D,

E,FandG.

• Note that the variables of equation which are x, y, and z in case of

Cartesian;r,t,andzincaseofCylindrical;andr,t,andpincaseof

SphericalCoordinateSystemshouldbeclosedinquotationmarks(““).

•Afterspecifyingtheequation,clickontheOKbuttonfromthedialog

box.

•ClickintheCoordinateSystemselectionboxandthenselectthedesired

coordinatesystemfromtheviewport.

•ClickontheOKbuttonfromthePropertyManagertoapplytheforce.

TorqueTechnicallyTorqueisproductofforceanddistance.Ifforceisappliedon

anobjectinsuchawaythatittendtorotatetheobjectthenitiscalled

torque.Thestepstoapplytorquearegivennext.

•ClickontheTorquebuttonfromtheExternalLoadsAdvisordrop-down.TheForce/Torque PropertyManager will be displayed with the Torque button

selectedbydefault.RefertoFigure-43.

•Selecttheroundfaceonwhichyouwanttoapplytorque.Previewofthe

torquewilldisplay;refertoFigure-44.

Figure-43.ForceTorquePropertyManagerwithtorqueoptions

Figure-44.Previewoftorqueapplied

• Specify the desired value of torque in the Torque Value edit box of

Force/Torquerollout.

• The other options in this PropertyManager are same as discussed for

force.ClickontheOKbuttonfromthePropertyManagertoapplytorque.

PressurePressureistheforceappliedperunitarea.Generally,weapplypressure

when we are analyzing pressure vessels or pipes. The steps to apply

pressurearegivennext.

• Click on thePressure option from theExternal LoadsAdvisor drop-down.ThePressurePropertyManagerwilldisplayasshowninFigure-45.

• Select the desired radio button from the Type rollout to specify thedirection of pressure. If you select the Use reference geometry radio

buttonthenonemoreselectionboxwillbedisplayedintheTyperolloutallowingyoutoselectthedirectionreference.

• Select the face on which you want to apply the pressure and enter the

desiredvalueofpressureintheeditboxdisplayedinthePressureValuerollout.

•IfyouhaveselectedtheUsereferencegeometryradiobuttonthenselectthedirectionreferencetospecifythedirectionofpressure.Previewof

thepressureappliedwillbedisplayed;refertoFigure-46.

•ClickontheOKbuttonfromthePropertyManagertoapplythepressure.Figure-45.PressurePropertyManager

Figure-46.Previewofpressureapplied

GravityGravityistheforceexertedbyearthoneachobjectinearthzone.Thisis

the force that causes objects to fall on the floor. TheGravity tool inSolidWorks Simulation is used to apply the gravity force on objects. The

stepstousethistoolaregivennext.

•ClickontheGravitytoolfromtheExternalLoadsAdvisordrop-down.TheGravityPropertyManagerwillbedisplayedasshowninFigure-47.

•Selecttheplane/face/edgetowhichdefinethedirectionofgravitational

force. Preview of the gravitational force will be displayed; refer to

Figure-48.

•Select/cleartheReversedirectionasperyourrequirement.Figure-47.GravityPropertyManager

Figure-48.Previewofgravitationalforce

•Ifyouwanttospecifymorecomponentsofgravitationalforcethenexpand

theAdvancedrolloutandenterthevaluesfortwootherdirectionvectorsofgravitationalforce;refertoFigure-49.

•ClickOKtoapplytheforce.

Figure-49.Previewofgravitationalforceadvanced

CentrifugalForceCentrifugal force is a force which causes the rotating objects to move

outward,seeaMary-go-round.IfyourunaMary-go-roundbeyonditsdesign

limits then you can see linked seats coming outward. This force is

generally generated by rotation of bodies. The steps to apply this force

aregivennext.

•ClickontheCentrifugalForcebuttonfromtheExternalLoadsAdvisordrop-down.TheCentrifugalPropertyManagerwilldisplayasshowninFigure-50.

Figure-50.CentrifugalPropertyManager

•Selecttheroundfaceonwhichyouwanttoapplythecentrifugalforce.

• Click in theAngularVelocity edit box and specify the angular velocityi.e.omegafortheobject.

• Click in the Angular Acceleration edit box and specify the value of

angularacceleration.Previewofthecentrifugalforcewilldisplay;refer

toFigure-51.

Figure-51.Previewofcentrifugalforce


BearingLoad

Bearing load is the load exerted by shaft floating in the inner ring of

bearing. The bearing load is applied on the round face of bearing and

shaft.Thestepstoapplytheloadaregivennext.

• Click on theBearingLoad option from theExternal Loads Advisor drop-down. The Bearing Load PropertyManager will be displayed as shown in

Figure-52.

Figure-52.BearingLoadPropertyManager

•Selectthefacesonwhichyouwanttoapplythebearingload.Notethat

youneedtoselecttwofaces,onefromshaftandonefrombearing.Also,

theselectedfacesmustbehalfofthefullface;refertoFigure-53.Note

thatyouwillneedtheSplitLinetooltodividethefaceofbearingandshaft.

Figure-53.Exampleforbearingload

•SpecifythevalueofloadinX-directionbyusingtherespectiveeditbox

inBearingLoadrollout.• If you want to apply load in Y-direction in place of X-direction then

clickonthe buttonandspecifythevalue.

•Ifyouwanttochangethedirectionasperyourrequirementthenclickin

thepinkselectionboxandselectthedesiredcoordinatesystem.

• Select theSinusoidal distribution orParabolic distribution radio button asperyourrequirement.

•ClickontheOKbuttonfromthePropertyManagertoapplythebearingload.

RemoteLoads/MassRemoteload/massisusedtoapplyforceonanobjectinsuchawaythatthe

originofforceissomewhereelsebutitisalsoaffectingontheselected

face;refertoFigure-54.

Figure-54.Remoteloadexample

If we apply this load in Solidworks Simulation then it will display as

showninFigure-55.

Figure-55.Remoteloadapplied

Theproceduretoapplyremoteloadisgivennext.

• Click on the Remote Load/Mass option from the External Loads Advisordrop-down. TheRemote Loads/Mass PropertyManager will be displayed asshowninFigure-56.

Figure-56.RemoteLoadsorMassPropertyManager

•SelectthedesiredradiobuttonfromtheTyperollouttospecifythetypeofremoteload/massyouaregoingtoapply.Notethatincaseofremote

load, the exact force working on the selected face is dependent on the

totalforceappliedontheactionpointanddistanceofactionpointfrom

the face. If you select theLoad (Direct transfer) radio button then theexactamountloadwhichcomesaftercalculationisappliedontheselected

faces.IfyouselecttheLoad/Mass(RigidConnection)radiobuttonthentheloadappliedontheselectedfaceactsliketheloadispassedwiththe

helpofrigidbarstotheselectedface.IfyouselecttheDisplacement(RigidConnection) radio button then it connects the remote location, atwhichtranslationandrotationsareapplied,tothecenteroftheselected

facesbyarigidbar.Theselectedentitiesdeformaccordingly.

•AfterselectingthedesiredradiobuttonfromTyperollout,clickontheUserDefinedradiobuttonfromtheReferenceCoordinateSystemrolloutand

thenselectareferencecoordinatesystemasrequired.Notethatyoucan

selecttheGlobalradiobuttontouseGlobalCoordinateSystemifyoudonotwishtoselectanyuserdefinedcoordinatesystem.

• Specify the location of remote point by using the edit boxes in the

LocationrolloutinthePropertyManager;refertoFigure-57.

Figure-57.Remoteloadlocation

•Similarly,specifythevalueofforceineachdirectionandthenclickon

theOK button from the PropertyManager to apply the forces. You canalso specify the moment of force by using the options in theMomentrollout.

DistributedMassUsingthisoption,youcanaddthemassoftheobjectsthatarenotcreated

inthemodelsbuttheirmasshaseffectsontheanalysis.Thestepstouse

thisoptionaregivennext.

•ClickontheDistributedMassbuttonfromtheExternalLoadsAdvisordrop-down.TheDistributedMassPropertyManagerwilldisplay;refertoFigure-58.

Figure-58.DistributedMassPropertyManager

•Selectthefaceonwhichyouwanttoaddmassofremoteobject.

• Click in theDistributed Mass edit box and specify the desired value.Previewoftheappliedmasswillbedisplayed;refertoFigure-59.

Figure-59.Previewofdistributedmass

• Click on the OK button from the PropertyManager to apply the

distributedmass.

Temperature

Thisoptionisusedtosettemperatureoftheselectedface.Thisoptionis

mostly used in thermal analyses. The steps to use this option are given

next.

• Click on the Temperature button from the External Loads Advisor drop-

down. TheTemperature PropertyManager will display as shown in Figure-60.

Figure-60.TemperaturePropertyManager

•Selectthefaceforwhichyouwanttosetthetemperature.

•ClickintheTemperatureeditboxoftheTemperaturerolloutandspecifythedesiredvalueintheeditbox.Previewoftheappliedtemperaturewill

bedisplayed;refertoFigure-61.

Figure-61.Previewoftemperature

•YoucanapplytemperatureonalltheexposedfacesbyselectingtheSelectallexposedfacesbutton.

FlowEffects/ThermalEffectsThese option are used to add the fluid flow or thermal effects in the

current study. The steps to specify the flow effect setting and thermal

effectsettingsaregivennext.

Figure-62.FlowThernalEffectstabofStaticdialogbox

•ClickontheFlowEffectsorThermalEffectsbuttonfromtheExternalLoadsAdvisordrop-down.AdialogboxwillbedisplayedwiththeFlow/ThermalEffectstabselected;refertoFigure-62.

• This dialog box is divided into two areas: Thermal options and Fluidpressureoptions.Theoptionsintheseareasarediscussednext.

ThermaloptionsTheoptionsinthisareaareusedtospecifythesourcefortemperaturesin

theactivestudy.Therearethreeoptionstodothat:

InputTemperatureSelectthisradiobuttontomanuallyspecifythetemperatureforthestudy.

Whenusingthisoption,makesuretospecifytemperaturesoncomponentsor

shells.Specifyingtemperaturesontheboundaryonlymaynotbepractical

since a temperature of zero is assumed at all other locations. If you

define temperature on boundary only, you may need to create and solve a

thermalstudyfirsttocomputetemperaturesatallnodes.

TemperaturesfromthermalstudySelectthisoptiontousetheoutputtemperatureofathermalstudyalready

performed.Onselectingthisradiobutton,theoptionsbelowitwillbecome

active. Select the desired thermal study from the drop-down to get is

outputtemperature.Youcanalsosetthetimeforgettingthetemperature

ataspecificpointoftime.Foratransientthermalstudy,selecteithera

Time step number (to import a single temperature) or For each nonlinear

time step, use temperature from corresponding time of transient thermal

analysis.

TemperaturesfromSolidWorksFlowSimulation

SelectthisoptiontousetheoutputtemperatureofacompletedSolidWorksFlowSimulationonthesameconfiguration.Clickonthisradiobuttonandthen click on the Browse button to select the result file of flow

simulation.Selectthedesiredresultfile(*.fld)thathasbeengenerated

by Flow Simulation. Model name, configuration name, and time step number

associatedwiththespecifiedfilearedisplayed.

ReferencetemperatureatzerostrainThiseditboxisusedtosetthetemperatureatwhichnostrainsexistin

themodel.

FluidpressureoptionTheoptionsinthisareaareusedtoimportsfluidpressureloadsfroma

SolidWorksFlowSimulationresultsfile.

IncludefluidpressureeffectsfromFlowSimulationSelectthisoptiontousetheoutputpressurefromacompletedSolidWorks

Flow Simulation results file. On selectin this option the Browse button

will become active below it. Click on the button and select the desired

resultfile(*.fld)thathasbeengeneratedbyFlowSimulation.Forproper

acquisition of pressure loads from Flow Simulation, the active study and

theFlowSimulationstudyshouldbeassociatedwiththesameconfiguration.Tocreatethe*.fldfile,clickFlowSimulation>Tools>ExportResults toSimulation.

Usereferencepressure(offset)in.fldfileSelect this option to use the reference pressure defined in the Flow

Simulationresultsfile.

Definereferencepressure(offset)Selectthisoptiontospecifyareferencepressuredirectly.Thispressure

valueissubtractedfromtheimportedpressurevalues.

Runaslegacystudy(excludeshearstress)Using this option, you can imports only the normal component of the

pressureloadfromtheFlowSimulation.

If you are analyzing an assembly, then you need to specify the type of

connections between various components of the assembly. The options to

specify connections for assembly are available in theConnectionsAdvisordrop-downwhichisdiscussednext.

CONNECTIONSADVISORThe options in this drop-down are used to apply various types of

connections between assembly components. You can also specify the

connections between components and ground by using these options. These

optionsarediscussednext.

ConnectionsAdvisorThis option is used to display the page of Simulation Advisor that is

relatedtoconnectionsbetweenassemblycomponents.Thestepstousethis

optionaregivennext.

•ClickontheConnectionsAdvisorbuttonfromtheConnectionsAdvisordrop-down in the Ribbon. The Simulation Advisor will be displayed with the

optionstoapplyconnections;refertoFigure-63.

Figure-63.SimulationAdvisorwithoptionsforconnections

•ClickontheNextbuttonfromtheSimulationAdvisor.Thelistofoptionsthatcanbeusedforconnectionsaredisplayed.

• Select the desired option and follow the instructions given by the

software. Note that these options are also available in the Connections

Advisordrop-downintheRibbon.Theoptionsarediscussedinthenext.

ContactSetsThisoptionisusedtospecifythecontacttypebetweentwocomponentsora

componentandground.Thestepstousethisoptionaregivennext.

•ClickontheContactSetsbuttonfromtheConnectionsAdvisor drop-down.TheContactSetsPropertyManagerwilldisplayasshowninFigure-64.

Figure-64.ContactSetsPropertyManager

•SelecttheAutomaticallyfindcontactsetsoptionfromtheContactrolloutifyouwantthesoftwaretoautomaticallydecidethetypeofcontacttobe

applied.

• Select theManually select contact sets option to specify the connectionsmanually.

• On selecting theManually select contact sets option, two selection boxeswillbecomeavailable.

• Select the desired option from the drop-down in theType rollout. Theoptionsinthisdrop-downandtheprocessofusingtheseoptionsaregiven

next.

NoPenetrationThisoptionisusedwhenyouwantthefacestobeintouchbyspecifiedgap

valuebutdonotwantthemtopenetratethrougheachother.Thestepsto

usethisoptionaregivennext.

•SelecttheNoPenetrationoptionfromthedrop-downintheTyperollout.TheoptionsinthePropertyManagerwillbedisplayedasshowninFigure-65.

Figure-65.OptionsinContactSetsPropertyManageronselectingNoPenetrationoption

• Click in the blue selection box and select the face/edge/point of the

firstpartthatyouwanttospecifyforconnection.

•Clickinthepinkboxandselecttheface/planeofsecondcomponentor

groundtocreatetheconnectionwith.

•ClickontheFrictioncheckboxandspecifythecoefficientoffrictionforcontact.

•ClickontheGap(clearance)checkboxandspecifythedesiredgapbetweenthetwocomponentsorcomponentandground.

•YoucanselecttheSelf-Contactcheckbox,ifyouwantyourobjecttonotintersectwithitselfundertheapplicationofforce;refertoFigure-66.

ThischeckboxisnewadditioninSolidWorks2015.

Figure-66.ResultofloadwithSelfContactcheckbox

•ClickonthecheckboxforAdvanced rollout and specify the method ofcontactbetweenthecomponentsbyselectingtheappropriateoption.

BondedThisoptionisusedtoattachonecomponenttotheothersuchthatboththe

componentsarepermanentlybondedtoeachother.Inotherwords,effectof

force on one component will also be passed on the bonded component

perfectly.Thestepstousethisoptionaregivennext.

• Select theBonded option from the drop-down in theType rollout. TheoptionsinthePropertyManagerwillbedisplayedasshowninFigure-67.

Figure-67.OptionsinContactSetsPropertyManageronselectingBondedoption

• Click in the blue box and select the face/edge/vertex of the first

component.

•Clickinthepinkboxandselecttheface/planeofthesecondcomponent.

Previewofthebondedconnectionwillbedisplayed;refertoFigure-68.

Figure-68.Previewofbondedconnection

• Click on the OK button from the PropertyManager to create the

connection.

AllowPenetrationThisoptionisusedallowpenetrationofoneobjectwiththeotherobject.

Notethatthisoptionisgenerallyusedwhentheobjectsareductile.The

stepstousedthisoptionaregivennext.

• Select the Allow Penetration option from the drop-down in the Typerollout.TheoptionsinthePropertyManagerwillbedisplayedasshowninFigure-69.

Figure-69.OptionsinContactSetsPropertyManageronselectingAllowPenetrationoption

• Click in the blue selection box and select the face/edge/vertex of the

firstcomponent.

•Clickinthepinkselectionboxandselecttheface/planeofthesecond

component.

•ClickontheOKbuttonfromthePropertyManager.

ShrinkFitShrinkfittingisaprocessinwhichashaftisinsertedinaholethatis

heatedup.Whenthehotholecoolsdownitstronglyarreststheshaftdue

tocontraction.Ifyouneedtospecifysuchaconnectionintheassembly,

thenthisoptionisused.Thestepstousethisoptionaregivennext.

•ClickontheShrinkFitoptionfromthedrop-downintheTyperolloutofPropertyManager. The PropertyManager will be displayed as shown in

Figure-70.

Figure-70.OptionsinContactSetsPropertyManageronselectingShrinkFitoption

•Youcanapplythisoptioninthesamewayasdiscussedearlier.Youcan

alsospecifyfrictioncoefficientbyselectingtheFrictioncheckbox.

VirtualWallUsingthisoption,youcanmakeacomponentattachedtoavirtualwall.In

this case, the body reacts as if it is in contact with a rigid/flexible

wall.Thestepstoapplythiscontactaregivennext.

•SelecttheVirtualWalloptionfromthedrop-downintheTyperollout.TheoptionsinthePropertyManagerwilldisplayasshowninFigure-71.

Figure-71.OptionsinContactSetsPropertyManageronselectingVirtualWalloption

•Selectthefacethatyouwanttoattachwiththevirtualwall.

•Clickinthevioletselectionboxtocollecttheplane.

•Selectthedesiredplanethatyouwanttomakeasvirtualwall.

•ClickontheGap(clearance)checkboxtospecifytheclearancegap.

•ClickontheRigidradiobuttontocreatearigidwallandspecifythefrictioncoefficientforthewallintheeditboxdisplayedinWallTyperollout.

•ClickontheFlexibleradiobuttontocreateaflexiblewall.• Specify the axial stiffness and tangential stiffness in the edit boxes

availableintheWallStiffnessrollout.

ComponentContactWhileworkingonanassembly,thisoptionisgenerallypreferredoverthe

otheroptionsavailableforconnections.Usingthisoption,youcanspecify

the contact between two or more bodies along their all shared faces. The

stepstousethisoptionaregivennext.

•ClickontheComponentContactbuttonfromtheConnectionsAdvisordrop-down.ThePropertyManagerwilldisplayasshowninFigure-72.

Figure-72.ComponentContactPropertyManager

•SelectthedesiredradiobuttonfromtheContactTyperollout.

•SelecttheGlobalContactcheckboxtoapplytheselectedcontacttypetoallthecomponentsoftheassemblyorselectthecomponentsonebyoneto

specifythecontacttype.

•IfyouhaveselectedtheNoPenetrationradiobuttonthenselectthecheckboxofFrictionrolloutandspecifythefrictioncoefficient.

• If you have selected the Bonded radio button from the Contact Typerolloutthenyoucanspecifythetypeofmeshforthecomponents.

•IfyouselecttheCompatiblemeshradiobuttonthenacombinedmeshforthe all the components bonded will be created. If you select the

Incompatiblemesh radio button then individual mesh will be created foreachofthebondedcomponents.

•ClickontheOKbuttonfromthePropertyManagertoapplythecontact.

ContactVisualizationPlotAfter applying various contacts on components of the assembly, you can

reviewthesecontactsbyselectingContactVisualizationPlotbuttonfromtheConnectionsAdvisordrop-downintheRibbon.Thestepstousethisoptionaregivennext.

•ClickontheContactVisualizationPlotbuttonfromtheConnectionsAdvisordrop-down. TheContact Visualization Plot PropertyManager will display as

showninFigure-73.

• Click on theCalculate button from the PropertyManager to display theconnections applied in the assembly. The list of connections will be

displayedintheResultsrollout.•FromSolidWorks2016onwards,youcannowchecktheunconstrainedbodies

in the assembly by using thisPropertyManager. To do so, click on theUnderconstrainedBodiestabfromthePropertyManager.TheoptionswillbedisplayedasshowninFigure-74.

Figure-73.ContactVisualizationPlotPropertyManager

Figure-74.ContactVisualizationPlotPropertyManagerwithUnderconstrainedBodiestab

• Click on theCalculate button to start analyzing the under-constrainedbodies. Once the analysis is done, click one by one on the degree of

freedomavailableforthebodyintheresultsareaofPropertyManagertocheck the constraining of objects. Note that you must have material

propertiesspecifiedtoallthecomponentsbeforeusingthisoption.

•ClickontheOKbuttonfromthePropertyManagertoexitthetool.

SpringThis option is used to connect two components in such a way that they

behave like joined by a spring. The steps to connect two components by

usingtheSpringbuttonaregivennext.

• Click on the Spring button from theConnections Advisor drop-down. TheSpringPropertyManagerwilldisplayasshowninFigure-75.

Figure-75.ConnectorsPropertyManagerwithSpringoption

• Select the desired spring type from theType rollout. There are threetype of springs available in the Type rollout; Compression-Extension,CompressionOnly,andExtensionOnly.

• Select the desired radio button from Flat parallel faces, Concentriccylindricalfaces,andTwolocationsradiobuttons.

•Selecttheentitiesaspertheselectedradiobutton.

•SpecifytheparametersrelatedtospringintheOptionsrollout.Previewofthespringwillbedisplayed;refertoFigure-76.

Figure-76.Previewofspringconnector

•ClickontheOKbuttonfromthePropertyManagertocreatethespringconnection.

PinThisoptionisusedtoconnecttwocylindricalcomponentswiththehelpof

theircircularfaces.Theassembliesthatconsistofmultiplepartscanbe

connected by the pin connector. Examples of assemblies with pins include

laptop flap joined with base, scissors lifts, pliers, and actuators. The

stepstousethisoptionaregivennext.

• Click on the Pin button from the Connections Advisor drop-down. The

ConnectorsPropertyManagerwillbedisplayedwiththeoptionsrelatedtopinconnector;refertoFigure-77.

Figure-77.ConnectorsPropertyManagerwithPinoption

•Selecttheroundfaceofthefirstobjectinassembly.

•Clickinthepinkselectionboxandselecttheroundfaceoftheother

objectintheassembly.

•SelectthedesiredcheckboxesfromtheConnectionTyperollout.

•SpecifytherelevantparametersintheAdvancedOptionrollout.

•SelecttheIncludeMasscheckboxtoincludethemassofthepin.Specifythemassofpinintheeditboxdisplayed.

•ClickontheStrengthDatacheckboxandselectthedesiredmaterialbyselectingtheSelectmaterialbutton.


connection.

BoltThisoptionisusedtosimulatetheboltconnectionbetweentwocomponents

oftheassembly.Ifyouhaveaddedtheboltsintheassemblybyusingthe

Toolboxthenyoucandirectlyconverttheboltintosimulationcomponentby

usingYesoptionfromthedialogboxdisplayedonselectingtheBoltoptionfrom theConnectionsAdvisor drop-down. The steps to use this option aregivennext.

• Click on theBolt option from theConnectionsAdvisor drop-down. If youhave added the bolts in the assembly by using the Toolbox. Then the

Simulationdialog box will be displayed as shown in Figure-78. Click ontheYesbuttontoautomaticallyapplythesimulationconnectionofbolt.

Figure-78.Simulationdialogbox

•IftheboltarenottakenfromtheToolboxoryouselecttheNobuttonfromtheSimulationdialogboxthentheConnectors PropertyManager willdisplaywiththeoptionsrelatedboltconnection;refertoFigure-79.

Figure-79.ConnectorsPropertyManagerwithBoltoption

•SelectthedesiredbuttonfromtheTyperollouttospecifythetypeofbolt.

•Selecttheroundedgeofthebolthead.

•Clickinthenextselectionboxintherolloutandselecttheroundedge

of the nut. Preview of the bolt connector will be displayed; refer to

Figure-80.

Figure-80.Previewofbotconnectorafterselection

•ClickontheTightFitcheckboxtoselectthefacewithwhichtheshankisincontinuouscontact.

• You can specify the material of the bolt by using the Select MaterialbuttonavailableintheMaterialrollout.Thenselectthedesiredmaterialtobeappliedfortheconnections.

•ClickontheStrengthDatacheckboxandspecifytherelatedparametersusingtheoptionsgivenintherolloutdisplayed.

•Youcanapplypreloadontheboltstosimulationtheeffectoftightened

nutsbyusingtheoptionsinthePre-loadrollout.

•Afterspecifyingthedesiredparameters,clickontheOKbuttonfromthe

PropertyManagertoapplytheconnection.

SpotWeldThis option is used to simulate the welding connection between two

componentsataspecificpoints.Theproceduretousethisoptionaregiven

next.

•ClickontheSpotWelds option from theConnectionsAdvisors drop-down.TheConnectorsPropertyManagerwillbedisplayedasshowninFigure-81.

•Selectthefirstfacethatyouwanttobewelded.

•Click in the next selection box in thePropertyManager and select thesecondface.

•Now,clickinthevioletselectionboxandselectthepointatwhichboth

theplatesmeeteachotherorwhereyouwantthespotweldconnectortobe

applied.

Figure-81.ConnectorsPropertyManagerwithSpotWeldsoption

•ClickintheSpotWeldDiametereditboxandspecifythediameterofthespotweldintheunitselectedindrop-down.

• Click on theOK button from the PropertyManager to create the weldconnection.

EdgeWeldThis option is used to simulate the welding connection between two

components at a common edge. The procedure to use this option is given

next.

Figure-82.EdgeWeldConnectorPropertyManager

•ClickontheEdgeWeldbuttonfromtheConnectionsAdvisordrop-down.TheEdgeWeldConnectorPropertyManagerwillbedisplayedasshowninFigure-82.

• Click on the first drop-down list in the Weld Type rollout in

PropertyManagerandselectthetypeoffillet/grooveyouwanttogenerateontheweldingbead.

• Select the first face for welding. Note that you can select only the

shell/surfaceorsheetmetalcomponentstoapplythisconnection.

•Clickinthenextselectionboxandselectthesecondfaceforwelding.

•ClickintheIntersectingEdgesselectionboxandselecttheedgeatwhichtheselectedtwofacesintersect.

•YoucansetthesizeofweldingbyusingtheoptionsintheWeldSizingrollout. You can also switch between American standard and European

standardofweldsizingbyselectingthecorrespondingradiobutton.

LinkThisoptionisusedtosimulatetheconnectionbetweentwocomponentslike

thetwocomponentsarelinkedattheirspecifiedpoints.Theprocedureto

usethisoptionisgivennext.

• Click on the Link button from the Connections Advisor drop-down. The

ConnectorsPropertyManagerwillbedisplayedasshowninFigure-83.•Clickonthedesiredpointoffirstentity.

•Clickinthevioletcoloredselectionboxandselectthesecondpointof

linkonthesecondentity.

•ClickontheOKbuttontocreatethelink.Notethatonspecifyingthe

linkconnector,thedistancebetweenthetwoselectedpointswillremain

thesame.

BearingThisoptionisusedtosimulatetheconnectionbetweentwocomponentslike

the two components are linked to each other with the help of a bearing.

Thisconnectionisgenerallyappliedtoshaftsandhousings.Theprocedure

tousethisoptionisgivennext.

•ClickontheBearingbuttonfromtheConnectionsAdvisor drop-down. TheConnectorsPropertyManagerwillbedisplayedwiththeoptionsrelatedtobearingconnection;refertoFigure-84.

Figure-83.ConnectorsPropertyManagerwithLinkoption

Figure-84.ConnectorsPropertyManagerwithbearingoption

•Selecttheroundfaceoftheshaft.

•ClickinthenextselectionboxintheTyperolloutandselecttheroundfaceofthehousing.

•SpecifythedesiredparametersintheStiffnessrolloutandclickontheOKbuttonfromthePropertyManagertoapplytheconnection.SeeFigure-85.

Figure-85.Previewofbearingconnection

RigidConnectionThisoptionisusedtoapplyrigidconnectionbetweenthetwocomponents.

Theproceduretocreatetherigidconnectionisgivennext.

• Click on theRigidConnection button from theConnectionsAdvisor drop-down. The Connectors PropertyManager will be displayed as shown in

Figure-86.

Figure-86.ConnectorsPropertyManagerwithrigidoption

•Selectthefirstfaceforapplyingrigidconnection.

•Clickinthenextselectionboxandselectthesecondadjoiningface.


connection.

After specifying the desired connections for the assembly/component, the

next step is to create and refine mesh for the assembly/component. The

methodstocreatemesharediscussednext.

MESHINGMeshing is the base of FEM. Meshing divides the solid/shell models into

elementsoffinitesizeandshape.Theseelementsarejoinedatsomecommon

pointscallednodes.Thesenodesdefinetheloadtransferfromoneelement

to other element. Meshing is a very crucial step in design analysis. The

automaticmesherinthesoftwaregeneratesameshbasedonaglobalelement

size,tolerance, and local mesh control specifications. Mesh control lets

youspecifydifferentsizesofelementsforcomponents,faces,edges,and

vertices.

The software estimates a global element size for the model taking into

consideration its volume, surface area, and other geometric details. The

size of the generated mesh (number of nodes and elements) depends on the

geometry and dimensions of the model, element size, mesh tolerance, mesh

control,andcontactspecifications.Intheearlystagesofdesignanalysis

where approximate results may suffice, you can specify a larger element

sizeforafastersolution.Foramoreaccuratesolution,asmallerelement

sizemayberequired.

Meshing generates 3D tetrahedral solid elements, 2D triangular shell

elements, and 1D beam elements. A mesh consists of one type of elements

unless the mixed mesh type is specified. Solid elements are naturally

suitable for bulky models. Shell elements are naturally suitable for

modelingthinparts(sheetmetals),andbeamsandtrussesaresuitablefor

modelingstructuralmembers.

Theproceduretocreatethemeshofthesolidisgivennext.

•ClickontheCreateMeshbuttonfromtheRundrop-downintheRibbon.TheMeshPropertyManagerwillbedisplayedasshowninFigure-87.

•Movetheslidertomaketheelementsofmeshfineorcoarse.Ifyoumove

theslidertowardstheright,theelementsofthemeshwillbecomefine.

Ifyoumovetheslidertowardstheleft,themeshwillbecomecoarse.

•SelecttheMeshParameterscheckboxtospecifytheparametersformesh.

•ClickontheCurvaturebasedmeshradiobuttonifyouwanttocreateacurvebasedmesh.

• Click on the Blended curvature-based mesh radio button if you want to

meshtheobjectalongblendedcurvature.Figure-88showsmeshingofaring

bythreemethods.

Figure-87.MeshPropertyManager

Figure-88.Meshtypes

•SelecttheAutomatic transitiontoapplymeshcontrolstosmallfeatures,holes, fillets, and other fine details of your model. Clear Automatic

transitionbeforemeshinglargemodelswithmanysmallfeaturesanddetailstoavoidgeneratinglargenumbersofelements.

•ClickontheAdvancedrollouttoexpandtheadvancedoptionsrelatedtothemesh.

• Jacobian points are used to specify the points on which the distortion

willbecreatedwhileperformingtheanalysis.TosettheJacobianpoints,

click on the drop-down in theAdvanced rollout and select the desirednumberofpoints.

•SelecttheDraftQualityMeshcheckboxtosetthequalityofmeshfor

fast evaluation of the analysis. If you select this check box then 4

corner nodes for solid and 3 corner nodes for each shell element are

created.

•Automatic trails for solidcheckboxisselectedtofindoutandapplytheoptimummeshsizeautomatically.Notethattheratiobywhichtheglobal

elementsizeandtolerancearereducedforeachtrialis0.8.Onselectingthis check box, the Number of trials spinner is displayed. Using this

spinner,youcanspecifythemaximumnumberoftrialsforre-meshing.

• If your part fails while meshing at some portions, then select the

Remeshfailedpartswith incompatiblemeshcheckboxtocreateincompatiblemeshattheportionsthatfailed.

•Ifyoudonotwanttoactuallymeshbutwanttosavethesettingsthen

selecttheSavesettingswithoutmeshingcheckbox.

• To run the analysis directly after creation of mesh, select the Run(solve)theanalysischeckbox.

Figure-89showsthemeshingofamodelwiththeloadsandfixturesapplied.

Figure-89.Previewofmeshwithloadsapplied

RUNNINGANALYSISAfter we have applied all the parameters related to analysis and we have

createdthemesh,thenextstepistoruntheanalysis.Thestepstorun

theanalysisaregivennext.

•ClickontheRunbuttonfromtheRibbon.Theanalyzingwillstartandtheresultwillbedisplayed;refertoFigure-90.

•Afterweruntheanalysis,thenextstepistointerprettheresultsof

theanalysis.Tointerprettheresultsforvariouspurposes,thetoolsare

availableintheResultAdvisorsdrop-downwhichisdiscussednext.Figure-90.Previewofsimulationresult

RESULTSADVISORThetoolsinthisdrop-downareavailableonlyafteryousuccessfullyrun

the desired type of analysis. The tools that get available after running

staticanalysisaregivennext.

•ResultsAdvisor

•ModelOnly(NoResults)

•NewPlotmenu

•ListStress,DisplacementandStrain

•ListResultForce

•ListContactForce

•ListPin\Bolt\BearingForce

Thetoolsabovearediscussednext.

ResultsAdvisorThis tool is used to display the result page of the Simulation Advisor;refertoFigure-91.ThestepstousetheoptionsinthispageofSimulation

Advisoraregivennext.

• Click on the Play button from the Simulation Advisor to plat the

simulationoftheappliedanalysis.Notethatthelimitsofdeflectionare

displayed in the Simulation Advisor. For example, in Figure-91, the

maximumdeflectionis2.29361e-005m.

•Afteryouhavecheckedthesimulation,youneedtochangetheparameters

ofmodeltogetthedesiredresults.Forexample,youwanttochangethe

materialtoincreasethestiffnessofthemodel.Toperformthesechanges,

weareprovidedwiththethreelinkbuttonsintheSimulationAdvisor.

• Click on the desired link button from the first three link buttons to

changetheparameters.Wewilldiscusstheseoptionslaterinthebook.

Figure-91.ResultspageSimulationAdvisor

ModelOnly(NoResults)This tool is used to display the model without displaying any result of

analysis.Useofthistoolsisverysimple,justclickonthetoolandthe

analysisresultwillhidautomatically.

NewPlotThe options in this cascading menu are used to generate new plots for

variousparametersonthebasisofperformedanalysis.IncaseofaStatic

analysis,youcangettheoptionsasshowninFigure-92.

Figure-92.OptionsinNewPlotcascadingmenu

The Stress, Strain and Displacement plots are added in the results

automatically.TheproceduretoaddFactorofSafetywillbediscussedin

next chapter. The procedures to add Design Insight, and Results Equation

plotsaregivennext.

DesignInsight• Click on the desired option from the menu. The respective

PropertyManagerwilldisplay;refertoFigure-93forDesignInsight.

Figure-93.DesignInsightPropertyManager

•SpecifythedesiredsettingsinSettingstabofthePropertyManagerandclick on the OK button display the desired type of analysis result;

refertoFigure-94.Notethatthelinkforselectedanalysisresultwill

beaddedintheResultsnodeintheleftarea.

Figure-94.Previewfordesigninsight

ResultsEquation•ClickontheResultsAdvisor->NewPlot->Results Equation option fromtheRibbon. TheResults Equation Plot PropertyManager will be displayedalongwiththeEditEquationdialogbox;refertoFigure-95.

Figure-95.ResultsEquationPlotPropertyManagerwithEditEquationdialogbox

• Select theNodeValues radio button or theElementValues radio buttonfromthedialogboxtomakeequationsfornodesorelementsinthemodel

respectively.

• Specify desired formula in the edit box like, “EPSX: X NormalStrain”+”EPSY:YNormalStrain”+”EPSZ:ZNormalStrain”tochecktriaxialstrainoneachnodeorelementintheresult.Notethatwhenyoutypea

mathematical operator or click in the empty edit box then a flyout is

displayed with equation parameters; refer to Figure-96. You can select

theseparametersforcreatingtheequation.

Figure-96.Flyoutwithequationparameters

•Aftercreatingequation,clickontheOKbuttonfromthedialogbox.

•EnterthedesirednameofplotintheLegendtitletexteditboxofEquationPlotOptionsrolloutofthePropertyManager.

•SelectthedesiredunitsystemfromtheUnitsdrop-downintherollout.

• Set the other parameters as required and then click on theOK button

fromthePropertyManager.Thenewplotwillbecreated;refertoFigure-97.NotethatthenewplotwillbeaddedintheResultsnodeattherightofthedialogbox.

Figure-97.Triaxialstrainplot

ListStress,DisplacementandStrainThistoolisusedtodisplaythevaluesofstress,displacementandstrain

at node intersecting with the selected plane. The procedure to use this

optionisgivennext.

• Select the plane by using which you want to check values of stress,

displacementandstrainattheintersectingnodes.

• Click on the List Stress, Displacement and Strain tool from the ResultsAdvisor drop-down. TheListResults PropertyManager will be displayed asshowninFigure-98.

• Select the desired radio button from theQuantity rollout. The optionsrelatedtotheselectedradiobuttonwillbedisplayedintheComponentrollout.Selectthedesiredcomponentofstress/displacement/strainfrom

thefirstdrop-downintherollout.

•ClickontheAdvancedOptionstoexpandtherollout.Theadvancedoptionsrelatedtotheselectedradiobuttonwillbedisplayed.RefertoFigure-

99.

Figure-98.ListResultsPropertyManager

Figure-99.ListResultsPropertyManagerwithexpandedAdvancedOptionsrollout

• Select the desired parameters from theAdvanced Options rollout to setthelimitsofdisplayedresult.

•ClickontheOKbuttonfromthePropertyManager.TheListResultsdialogboxwillbedisplayed;refertoFigure-100.

•ClickontheSavebuttontosavetheresultsinaCSVexcelfile.ClickontheClosebuttontoclosethedialogbox.

Figure-100.ListResultsdialogbox

ResultForceThis tool is used to display the reaction forces resulting due to the

appliedload.Thestepstousethistoolaregivennext.

• Click on theResult Force tool from theResults Advisor drop-down. The

ResultForcePropertyManagerwillbedisplayedasshowninFigure-101.

•SelectthedesiredradiobuttonfromthePropertyManager.•Clickintheblueselectionboxandselecttheface/edge/pointatwhich

youwanttocheckthereactionforces.

• Select the desired unit system from the Unit drop-down in the

PropertyManager.

• Click on the Update button from the PropertyManager to display the

reaction forces. The box containing values of reaction forces will be

displayedwiththemodel;refertoFigure-102.

Figure-101.ResultForcePropertyManager

Figure-102.Previewofresultforce

•ClickontheOKbuttonfromthePropertyManagertoexitthetool.

IfyouhaveappliedcontactforcesorPin/Bolt/Bearingforces,thenclick

ontherespectivetoolfromtheResultsAdvisordrop-down.Theresultwillbedisplayedinthesamewayasdiscussedearlier.

We will learn about more options related to results while performing the

analysesinsubsequentchapters.

SELF-ASSESSMENT

Q.1Wecanperformstaticanalysisonobjectswithoutapplyingmaterialto

object.(T/F)

Q2.Ifyoudonotapplyfixturesthentheobjectwillbefreetomovein

thedirectionofforcesappliedandnostressorstrainwillbeinducedin

it.(T/F)

Q3.UsingtheFixedGeometryfixturetype,youcanfixtheface,edgeor

pointoftheobject.(T/F)

Q4.TheFixedHingetoolisusedtofixafaceinsuchawaythatitcanslide/rollinitsplanebutcannotmoveperpendiculartotheplane.

Q5.Aliveexampleofelasticsupportfixturecanbeanobjectplacedon

wood,rubberoranyspringbase.(T/F)

Q6. Which of the following fixture option makes the object move in

specifieddirectionandrestrictsmotioninotherdirections?

a.UseReferenceGeometry

b.CyclicSymmetry

c.ElasticSupport

d.Roller/Slider

Q7.WhichofthefollowingrolloutinForce/TorquePropertyManagerisusedtodefineequationfornon-uniformforcedistribution?

a.Force/Torque

b.NonuniformDistribution

c.SymbolSettings

d.Selection

Q8.…………….isproductofforceanddistance.

Q9.…………..isforceappliedperunitarea.

Q10. …………. force is a force which causes the rotating objects to move

outwardoftheircircularpath.

PreparingModelforAnalysis

Chapter3

TopicsCovered


•CreatingReferenceGeometry

•SimplifyingModelforAnalysis

•ExtrudeandRevolveTool

•SplittingFacesandBody

•GeneratingMidSurface

•AddingandSubtractingBodies

•ImportingParts

INTRODUCTIONNoPal!Youcannotrunanalysisdirectlyonamodelwhichhasfilletsand

other feature. The features like fillet, chamfer, holes (which are not

playingroleinanalysis)etc.increasethesolutiontimeanderrorofthe

analysis. So, we need to de-feature the model before running analysis in

SolidWorksSimulation.ThereisaseparateCommandManagerinSolidWorksto simplify model called Analysis Preparation CommandManager; refer to

Figure-1.

Figure-1.AnalysisPreparationCommandManager

Youcanperformmanyothertasklikefindingmid-surface,splittingfaces,

creatingreferencefeaturesetc.usingthetoolsinthisCommandManager.ThemostcommonlyusedtoolsinthisCommandManageraregivennext.

REFERENCEGEOMETRYThere are various types of reference geometries that can be created in

SolidWorks. All the tools to create these reference geometries are

availableintheReferenceGeometrydrop-down;refertoFigure-2.Thetoolsavailableinthedrop-downare:

•Plane

•Axis

•CoordinateSystem

•Point

•CenterofMass

•MateReference

Figure-2.Referencedrop-down

Thesetoolsarediscussednext.

PlaneThePlane tool is used to create reference planes. By default there arethreeplanesavailableinSolidWorks:Front,Top,andRight.Tocreatemoreplanesfollowthestepsgivennext.

•ClickonthePlanetoolfromtheReferenceGeometrydrop-down.ThePlanePropertyManagerwilldisplayasshowninFigure-3.

Figure-3.PlanePropertyManager

•Youcanselectmaximumthreereferencestocreateaplane.Youcanselect

plane/face, edge/axis/curve, or vertex/point. The ways in which you can

createplanesbyusingthesereferencesarediscussednext.

Creatingplaneatadistancefromplane/face•Tocreateaplaneatadistancefromaplane/face,selecttheplane/face.

TheupdatedPlanePropertyManagerwilldisplayasshowninFigure-4.•Specifythedesireddistanceinthespinner.

•ClickontheOKbuttontocreatetheplane.

Figure-4.UpdatedPlanePropertyManager

Creatingplaneatanangletoplane/face•ActivatethePlanePropertyManagerandselectaplane/facetowhichyouwanttospecifytheangle.

•ClickontheAtAnglebuttontospecifytheangle.

•ClickintheSecondReferenceboxandselecttheedgeoraxistowhichyouwanttomaketheplanecoincidentorselectthetwoplanarpointthrough

whichyouwanttheplanetopass.Figure-5showstheplanecreatebyboth

themethodsdiscussed.

Figure-5.Planecreationatangle

Creatingplanepassingthroughpoints• Activate the Plane PropertyManager and one by one click three pointsthroughwhichyouwanttheplanetopassthrough.Figure-6showstheplane

passingthroughthreepoints.

Figure-6.Planepassingthroughthreepoints

PlaneParalleltoScreenThis option is a new feature of SolidWorks 2016. The procedure to create

planeparalleltoscreenisgivennext.

•Right-clickonanyface,edge,orvertexofthemodel.Ashortcutmenu

willbedisplayed;refertoFigure-7.

Figure-7.Shortcutmenuonrightclickingonaface

•ClickontheCreatePlaneParalleltoScreenoptionfromtheshortcutmenu.Aplaneparalleltoscreenwillbecreated;refertoFigure-8.

Figure-8.Planeparalleltoscreen

AxisThe Axis tool is used to create reference axes. An axis is useful in

creating revolve features or to create planes at angle. To procedure to

createaxisbyusingtheAxistoolisgivennext.

• Click on the Axis tool from the Reference drop-down. The AxisPropertyManagerwilldisplayasshowninFigure-9.

•SelectthedesiredbuttonfromthePropertyManager.ThebuttonsinthisPropertyManagerareexplainednext.

Figure-9.AxisPropertyManager

OneLine/Edge/AxisSelectthisbuttonifyouwanttocreateanaxiscoincidenttotheselected

line/edge/axis. After selecting this button, click on the line/edge/axis.

Theaxiswillbecreatedcoincidenttotheselectedline/edge/axis;refer

toFigure-10.

Figure-10.Axiscreatedonedge

TwoPlanes

SelecttheTwoPlanesbuttonifyouwanttocreateaxisattheintersectionofthetwoselectedplanes/faces.Afterselectingthisbutton,clickonthe

two intersecting. The axis will be created at the intersection; refer to

Figure-11.

Figure-11.Axisatintersectionofplanes

TwoPoints/VerticesSelect the Two Points/Vertices button if you want to create axis passingthroughtheselectedtwopoints/vertices;refertoFigure-12.

Figure-12.Axispassingthroughtwopointsorvertices

Cylindrical/ConicalFaceSelect theCylindrical/Conical Face button and select a cylindrical/conicalface. An axis passing through center of cylindrical/conical face will be

created;refertoFigure-13.

Figure-13.Axisthroughcylinderandconical

PointandFace/PlaneSelectthePointandFace/Planebuttonifyouwanttocreateanaxispassingthroughtheselectedpointandperpendiculartotheselectedface/plane.

CoordinateSystemTheCoordinateSystemtoolisusedtocreatereferencecoordinatesystem.

Thestepstocreatecoordinatesystemareexplainednext.

• Click on theCoordinate System tool from theReference drop-down. TheCoordinateSystemPropertyManagerwilldisplayasshowninFigure-14.

Figure-14.CoordinateSystemPropertyManager

•Clickonthepointwhereyouwanttoplacethecoordinatesystem.

•Clickintheboxforwhichyouwanttospecifydirectionreferenceand

select the reference like plane, axis and so on. Figure-15 shows a

coordinatesystemcreatedontheface.

Figure-15.Coordinatesystemcreation

PointThePointtoolisusedtocreatereferencepointsonthemodel.Thestepstocreatepointsaregivennext.

• Click on the Point tool from the Reference drop-down. The PointPropertyManagerwilldisplayasshowninFigure-16.

• Select the desired button to specify the type of point you want to

create.Inthiscase,wehaveselectedCenterofFacebutton.• Select the reference (face of the model in this case). Preview of the

pointwilldisplay;refertoFigure-17.

Figure-16.PointPropertyManager

Figure-17.Previewofpoint

•ClickontheOKbuttontocreatethepoint.

Youcancreatearrayofpointsalongacurvebyselecting button.

CenterofMassTheCenterofMasstoolisusedtodisplaythecenterofmassofthemodel.The coordinates of center of mass are generally required in some

calculationsrelatedtoinertiaoftheobjects.Identificationofcenterof

massisalsohelpfulincheckingthestabilityofobjectinconstraintfree

environment.Todisplaythecenterofmass,clickontheCenterofMasstoolfrom theReference drop-down and the center of mass will display in theviewport;refertoFigure-18.

Figure-18.Centerofmassofcylinder

SIMPLIFY

TheSimplifytoolisusedtoremovethefeaturesthatareofnoimportanceinthecurrentanalysis.Theproceduretousethistoolisgivennext.

•ClickontheSimplifytoolfromtheAnalysisPreparationCommandManager.TheSimplifytaskpanewillbedisplayedattherightintheapplicationwindow;refertoFigure-19.

Figure-19.Simplifytaskpane

•ClickintheFeaturesdrop-downoftaskpaneandselectthecheckboxesoffeaturesthatyouwanttobesimplified.

• Specify the desired simplification factor in the Simplification factorspinner and select the radio button below it to set the simplification

factortype.

• Click on the Find Now button to search for the features that can besimplifiedbasedonyourinputs.Thefeaturesthatcanbesimplifiedor

saysuppressedaredisplayedintheResultsareaofthetaskpane.•Selectthefeaturesthatdonothaveanyeffectonyouranalysiswhile

holdingCTRLkey;refertoFigure-20.

Figure-20.Featurestobesimplified

•Specifythenameofnewconfigurationofpart/assemblytobecreatedwith

suppressedfeaturesintheNameeditboxatthebottomofthetaskpane.MakesuretheCreatederivedconfigurationcheckboxisselected.

• Click on the Suppress button at the bottom in the task pane. A new

configurationwith suppressedfeatures will be created on which you can

performtheanalysis;refertoFigure-21.

Figure-21.Simplifyingmodel

EXTRUDEDBOSS/BASETOOLExtrudedBoss/Basetoolisusedtocreateasolidvolumebyaddingheighttotheselectedsketch.Inotherwords,thistooladdsmaterial(byusingthe

boundaries of sketch) in the direction perpendicular to the plane of

sketch.InthetermBoss/Base;theBasedenotesthefirstfeatureandBoss

denotes the feature created on any other feature. The steps to create

extrudedfeatureisgivennext.

• Click on the Extruded Boss/Base tool from the Ribbon. The ExtrudePropertyManagerwilldisplay;refertoFigure-22.

Figure-22.ExtrudePropertyManager

•Selectaplanefromtheplanesdisplayedintheviewport.Thesketching

environmentwilldisplaywiththesketchtoolsactivated.

•CreateaclosedsketchandthenclickontheExitSketchbuttonfromtheviewportasshowninFigure-23.YoucanalsoselecttheExitSketchbuttonfromtheRibbon.TheBoss-ExtrudePropertyManagerwilldisplayasshowninFigure-24.

Figure-23.Sketchenvironmentofextrude

Figure-24.Boss-ExtrudePropertyManager

•ClickontheStartingreferencedrop-downandselectthedesiredoption.

Therearefouroptionsinthisdrop-down;SketchPlane,Surface/Face/Plane,Vertex, andOffset. The Sketch Plane is selected by default. Select thisoptionifyouwanttheextrusiontostartfromsketchingplane.Selectthe

Surface/Face/Plane option to start the extrusion from the selected

surface/face/plane. Select the Vertex option to start extrusion from

selectedvertex.SelecttheOffsetoptionifyouwanttostartatspecifieddistancefromthesketchingplane;refertoFigure-25.

Figure-25.Previewofoffsetoption

•ClickintheLimitingreferencetypedrop-downandselectthereferencefor

endofextrusion.

Therearesixoptionsinthedrop-down;Blind,UpToVertex,UpToSurface,OffsetFromSurface,UpToBody,andMidPlane.IfyouhaveselectedBlindorMidPlane option, then you need to specify the distance value in theHeight of extrusion spinner. If you have selected any of the other optionthen select the respective reference from the viewport. Figure-26 shows

previewofextrusionbyusingtheMidPlaneoption.NotethatifMidPlaneoptionisselectedthentheDirection2rolloutwillnotdisplay.

Figure-26.Mid-Planeextrusion

•ClickintheDirectionofextrusionselectionboxandselectthereferenceif you do not want to extrude perpendicular to the sketching plane and

wanttoextrudealongselectedaxis/plane

• Click in the edit box for extrusion height and enter the desired

extrusionheightoryoucansetthevaluebyusingspinner.

• Click on theDraftOn/Off button to apply draft angle on the verticalfacesofthemodel.Onselectingthisbutton,1°draftwillbeappliedbydefaulttakingthesketchingplaneasreference.SelecttheDraftoutwardcheck box to apply draft angle outwards on the vertical faces of

extrusion.SpecifythedraftangleintheDraftAnglespinner.

The parameters you specified above can also be applied to the opposite

direction.Toapplytheseparameters,selecttheDirection2checkbox.Theparametersfortheoppositedirectionwilldisplay.

• Select theThin Feature check box to create the thin walled extrusion.EnterthethicknessintheThicknesseditboxoftheThinFeaturerollout.Figure-27showsathinfeaturedextrusion.Notethatifopensketchisselectedforextrudethenthisoptiongetsselectedautomatically.

Figure-27.ThinFeatureextrusion

•Ifyouwanttoclosethestartandendfaceoftheextrusionthenselect

theCapEndscheckbox;refertoFigure-28.

Figure-28.Extrusionwithcapends

•Onceyouhavefinishedcreatingthefeature,clickontheDetailedPreviewbuttonfromthePropertyManagertoverifythefeature;refertoFigure-29.

Figure-29.DetailedPreviewbutton

• Select the Highlight new or modified faces check box if you want to

highlightthenew/modifiedfacesonly.Similarly,youcanselecttheShowonly new ormodifiedbodiescheckboxifyouwanttodisplayonlynewormodifiedobjects.

InSolidWorks2017,youcanalsoactivatetheExtrudeBoss/BasetoolbyALTkey. To do so, press the ALT key from keyboard and click on the shaded

sketch section in the Sketching environment. The Extrude button will bedisplayed; refer to Figure-30. Click on the Extrude button to display

Extrude PropertyManager. Rest of the procedure is same as discussed

earlier.

Figure-30.Alternatemethodforextrude

REVOLVEDBOSS/BASETOOLRevolved Boss/Base tool is used to create a solid volume by revolving asketchaboutselectedaxis.Inotherwords,ifyourevolveasketchabout

anaxisthenthevolumethatissweptbyrevolvedsketchboundaryiscalled

revolvedboss/basefeature.Thestepstocreaterevolvedboss/basefeature

aregivennext.

• Click on the Revolved Boss/Base tool. If you have not selected any

existing sketch, then theRevolve PropertyManager displays as shown inFigure-31.

Figure-31.RevolvePropertyManager

•Selectaplaneifyouwanttocreateanewsketchorselectanalready

createdsketch.Inourcase,weareselectinganalreadycreatedsketch.

• Select the region of the sketch that you want to revolve if you have

multiple loops in sketch; refer to Figure-32. The updated RevolveProperyManagerwilldisplayasshowninFigure-33.

Figure-32.Regionselectedforrevolve

Figure-33.UpdatedRevolvePropertyManager

•ClickintheAxis ofRevolutionselectionboxtoselecttheaxis.Selecttheedge,line,orcenterlineaboutwhichyouwanttorevolvethesketch.

Previewoftherevolvefeaturewilldisplay;refertoFigure-34.

Figure-34.Previewofrevolvefeature

•ClickontheRevolveTypedrop-downandspecifytherevolutionlimitingreference. The options in this drop-down are same as discussed for

ExtrudedBoss/Basetool.

• If you have selected Blind option in the Revolve Type drop-down then

specifythedegreesofrevolutionbyusingtheAnglespinner.

•ClickontheDirection2 check box to revolve in the direction oppositethe earlier on. The options in the Direction 2 rollout are same as

discussedearlier.

•YoucanalsocreatethinfeaturebyselectingtheThinFeaturecheckbox.Notethatifyouselectanopensketchthenthisoptionisautomaticallyselected.

•ClickintheSelectedContoursboxtoaddmoresketchesforrevolutionandselectthesketchesyouwanttorevolve.

Figure-35showsasketch,axisofrevolution,andresultingrevolvefeature

preview.

Figure-35.Revolvedfeature

EXTRUDEDCUTTheExtrudeCut tool is used to remove material by extruding the sketch.Thestepstousethistoolaregivennext.

• Click on the Extruded Cut tool. The Cut-Extrude PropertyManager willdisplay.

•Selectthefacefromwhichyouwanttostartremovingthematerial.The

sketchenvironmentwillactivate.

•Clickthesketchusingwhichyouwanttoremovethematerial.

• Click on the Exit Sketch button from the Ribbon. The preview of cut

featurewilldisplay;refertoFigure-36.

Figure-36.Previewofextrudecutfeature

• Specify the depth of material removal and other parameters in the

PropertyManagerasdiscussedforExtrudeBoss/BasetoolandthenclickontheOKbutton.

MIRRORTheMirror tool is used to create mirror copy of the features in the

Modelingenvironment.Theproceduretocreatemirrorisgivennext.

•Selectallthefeaturesthatyouwanttomirror.

•ClickontheMirrortoolfromtheAnalysisPreparationCommandManagerin the Ribbon. The Mirror PropertyManager will display as shown in

Figure-37.

• Select the plane or face about which you want to mirror the features.

Previewofthemirrorwillbedisplayed;refertoFigure-38.

•ClickontheOKbuttonfromthePropertyManagertocreatethefeature.Figure-37.MirrorPropertyManager

Figure-38.Previewofmirror

Ifyouwanttomirroracompletebodywithrespecttomirrorplaneasin

theabovefigure,thenfollowthestepsgivennext.

•ClickontheMirrortool.TheMirrorPropertyManagerwilldisplay.

• Expand the Bodies to Mirror rollout and click on the bodies in the

viewportthatyouwanttomirror.

•ClickintheMirrorFace/PlaneboxintheMirrorFace/PlanerolloutoftheProperyManager and select the mirror plane. Preview of mirror will

display; refer to Figure-39. Make sure that you clear theMerge solidscheckboxbeforecreatingthemirrorcopy.

•ClickontheOKbuttontocreatethemirrorcopy.

Figure-39.Previewofbodymirror

SPLITLINETOOLInsomeofthecases,youneedtoapplyloadorconstraintataconfined

areaoffaceratherthenthefullarea.Inthatyoucase,youneedtosplit

theface.Thestepsgivennextexplaintheprocedureofsplitting.

• Click on the Split Line tool from the Ribbon. The Split LinePropertyManagerwillbedisplayedasshowninFigure-40.

Figure-40.SplitLinePropertyManager

•Bydefault,Projectionradiobutton is selected and you aresupposedtoselectasketchfordividingtheface.Figure-41showsapartthatneedto

bedividedfrommid.

Figure-41.Parttobesplitted

•AlinesketchisdrawnatthecenterofthemoldpartonRight-planeso

thatitcandividethepartintotwopieces;refertoFigure-42.

Notethattodrawthesketch,youneedtocanceltheSplitLinetool,selectthe Sketch CommandManager from the Ribbon and after you draw the

sketch,youneedtoselecttheSplitLinetoolagain.

Figure-42.Sketchedlinedrawnatthecenter

•Selectthelinesketch,itwillbedisplayedinthefirstselectionbox

intheSplitLinePropertyManager.•Clickinthenextselectionbox.Youwillbeaskedtoselectthefacesto

besplitup.

• Select all the faces of the part that you want to split by using the

projectionofsketch;refertoFigure-43.

• Select the OK button from the PropertyManager, the part will be

displayedasshowninFigure-44.

Figure-43.Facesselected

Figure-44.Partaftersplitting

• You can also split this part by using the Silhouette radio button. Butthat will be based on the mold analysis which is out of scope of this

book. In the same way, you can split the part by using the Intersectionradiobutton;refertoFigure-45.

Figure-45.Splittingbyintersection

MIDSURFACETheMid Surface tool is used to create a surface at the mid of selectedfacesofthepart.Youmayaskwhatisthebenefitofthisforsimulation.

Mostofthetimewhenyouremoveextrafeaturesfromyourmodel,themodel

isaplanepieceofmetalwithdifferentthicknessesatdifferentplaces.

Whenyouperformanalysisonasolid,thenumberofelementsduringmeshing

areveryhighduetostackingofelementsalongZdirectionapartfromX

and Y directions. If you create mid surface of solid and apply thickness

usingtheShellManagerthennumberofelementsarereduced.Inturn,thetime taken by analysis is reduced. When you apply thickness using ShellManager then 3D model of part remains in surface but while solving

analysis equation, value of thickness is applied in equations

automatically.TheproceduretocreateMidsurfaceisgivennext.

• Click on the Mid Surface tool from the Analysis PreparationCommandManager. The MidSurface PropertyManager will be displayed;

refertoFigure-46.Also,youwillbeaskedtoselectthefirstfacefor

creatingmid-surface.

Figure-46.MidSurfacePropertyManager

• Select the first face of the model. You will be asked to select the

secondfaceofthemodelincurrentset.

•Selectthesecondface,asetwillbecreatedintheFacepairsselectionbox;refertoFigure-47.

Figure-47.Faceselectionformidsurface

•AfterselectiontheFace1andFace2selectionboxeswillbecomeemptypromptingyoutoselectthenextset.

•Ifyouwanttofindthefacepairsautomaticallyformidsurfacethendo

not select any face manually. In the Recognition Threshold drop-down,

selectthedesiredoperatorandthenspecifythevalueofthresholdinthe

edit box next to it. Click on the Find Face Pairs button from the

PropertyManager.Mostofthefaceswillgetselectedautomatically;refertoFigure-48.

Figure-48.Facepairsselectedautomatically

•Selecttherestofthefaceasdiscussedearlierifrequired.

• Set the position of the mid-surface using the Position spinner. If thepositionvalueis50%thenmidsurfacewillbecreatedatthecenterofthefacepairs.

•ClickontheOKbuttonfromthePropertyManagertocreatethesurface.Hiderestofthefeaturetocheckthemid-surface;refertoFigure-49.

Figure-49.Solidtomidsurface

SPLITTOOL

TheSplittoolisusedtocreatemultiplebodiesofasolidbodybyusingatrimmingtool.Theproceduretousethistoolisgivennext.

•ClickontheSplittoolfromtheAnalysisPreparationCommandManagerintheRibbon.TheSplitPropertyManagerwillbedisplayed;refertoFigure-50.

Figure-50.SplitPropertyManager

• Select the plane/surface/sketch to be used as trimming tool. Note that

theplane/surfaceshouldintersectthepart.

•ClickontheCutPart tool from thePropertyManager. The part will beseparatedintomultiplebodies.

•SelectthecheckboxesfromtheResultingBodiesrollouttocreatesplits.

•SelecttheConsumecutbodiescheckboxtoconsumethebodyselectedintheResultingBodiesrollout.

• Select the Propagate visual properties check box to apply the same

propertiestothesplitbodieswhichwereappliedtothemainbody.


COMBINETOOLTheCombine tool is used to add/subtract two or more solid bodies. Theproceduretousethistoolisgivennext.

• Click on the Combine tool from the Analysis PreparationCommandManager.TheCombinePropertyManagerwillbedisplayed;refertoFigure-51.

Figure-51.CombinePropertyManager

AddingSolidBodies•SelecttheAddradiobuttonfromtheOperationTyperolloutandselectallthebodiesthatyouwanttobecombined.

•ClickontheOKbuttonfromthePropertyManagertocombinebodies.

SubtractingSolidBodies• Select the Subtract radio button from the Operation Type rollout and

selectthemainbodyfromwhichyouwanttosubtractothersolidbodies.

Youwillbeaskedtoselectthebodiestobesubtracted.

•Selectthebodiesthatyouwanttobesubtractedfromthemainbody.


INTERSECTTOOLThe Intersect tool is used to intersect solids, surfaces, or planes to

modify existing geometry or create a new geometry of intersection

boundaries.Theproceduretousethistoolisgivennext.

•ClickontheIntersecttoolfromtheAnalysisPreparationCommandManager.TheIntersectPropertyManager will be displayed; refer to Figure-52. Youwillbeaskedtoselectthebodieswhichareintersecting.

Figure-52.IntersectPropertyManager

• Select the intersecting solids, surfaces, or planes which are forming

closedsection.

• Select the desired radio button from the PropertyManager to create

desiredregionsafterintersection.

•Clickonthe IntersectbuttonfromthePropertyManager. Various regionsof the solid will be displayed in the drawing area as well as in the

RegiontoExcluderollout;refertoFigure-53.

Figure-53.Regionscreatedfromsolid

• Select the check box from the Region to Exclude rollout to exclude

selectedregion.

•Ifyouwanttomergeallthecreatedregionstoformonebodythenselect

theMergeresultcheckboxfromOptionsrolloutofthePropertyManager.

• Similarly, select the Consume surfaces check box to delete the

interestingsurfacesaftercreatingtheregions.


body/regions.

MOVE/COPYBODIESTOOLTheMove/Copy Bodies tool is used to move or copy selected bodies. Theproceduretousethistoolisgivennext.

• Click on the Move/Copy Bodies tool from the Analysis PreparationCommandManager.TheMove/CopyBodyPropertyManagerwillbedisplayedasshowninFigure-54.

Figure-54.Move/CopyBodyPropertyManager

•Selectthebody/bodiestobemovedorcopied.Atriadforrotating/moving

the part will be displayed. Drag or rotate the triad using respective

handlestomove/rotate.

• To move the body/bodies by desired distance, click in the TranslateReference selection box from the Translate rollout and select a

point/edge/coordinatesystemfordirectionreference.Specifythedesired

distancevaluesintherespectiveeditboxesofTranslaterollout.

• Expand theRotate rollout in the PropertyManager and set the desiredrotationvaluesasrequired.

•ClickontheOKbuttonfromthePropertyManagertoapplythechanges.

Similarly,youcanusetheDelete/KeepBodytool.Ifyoufindanydoubtinworkingwiththistoolpleaseemailme.

OthertoolsofSolidWorksarediscussedinourbook:SolidWorks2017BlackBook.

IMPORTINGPART•ClickontheOpenbuttonfromtheQuickAccessToolbar or press CTRL+O

fromthekeyboard.TheOpendialogboxwillbedisplayed.

•Double-clickonthedesiredfilethatyouwanttoopen.MakesuretheAllFilesordesiredfiletypeisselectedintheFileType drop-down in thedialog box; refer to Figure-55. The respective SOLIDWORKS Converterdialogboxwillbedisplayed;refertoFigure-56.

Figure-55.FileTypedrop-down

Figure-56.SOLIDWORKSConverterdialogbox

• Select the Import geometry directly radio button and select the desiredradiobuttontoimportthegeometriesofselectedfile.Ifyouselectthe

BREP radio button the model is imported as solid with Boundary

Representation data. If you select the Knitting radio button then the

modelwillbeimportedassurfacesknittedtogetherandifyoualsoselect

theTry forming solidmodel(s)checkboxthensystemwillformasolidifsurfaceformclosedboundaries.IfyouselecttheDonotknitthesurfaces

willbeimportedinSolidWorks.

•IfyouwanttoSolidWorkstorecogniseasmanyfeaturesaspossiblein

theimportedmodelthenselecttheAnalyzethemodelcompletelyradiobuttonfromthedialogbox.

•Selectthedesiredcheckboxesfromthedialogboxtoimportrespective

parametersofthemodel.

•ClickontheOKbuttonfromthedialogbox.IfyouselectedtheAnalyze

themodelcompletelyradiobuttonearlierthenaninformationboxwillbe

displayed; refer to Figure-57. Click on theBody button and select thedesiredcheckboxes.TheSOLIDWORKSdialogboxwillbedisplayedasshowninFigure-58.

Figure-57.Informationbox

Figure-58.SOLIDWORKSdialogbox

Figure-59.ImportDiagnosticsPropertyManager

•ClickontheYesbuttonfromthedialogboxtostartimportdiagnosticwhich help in finding any inconsistency of imported model. The ImportDiagnosticsPropertyManagerwillbedisplayed;refertoFigure-59.

• Click on the Attempt to Heal All button to heal the faces/gaps. The

faces/gaps which are not able to heal automatically should either be

deletedorremodelled.

•ClickontheOKbuttonfromthePropertyManagertosolveproblemsofimportedparts.

StaticAnalysis

Chapter4

TopicsCovered


•StartingStaticAnalysis.

•ApplyingMaterial.

•DefiningFixtures

•Applyingloads


•SimulatingAnalysis.


LINEARSTATICANALYSISLinear static analysis is performed to calculate stresses, displacements,

strains,forces, anderror estimatesunder variousloading conditions. On

applying the loads, the body gets deformed and the loads are transmitted

throughoutthebody.Thedeformationandothereffectsofbodyarestudied

underthisanalysis.

AssumptionsSomeassumptionsaremadeinthistypeofanalysis,like:

1.Theloadsapplieddoesnotvarywithtime.

2.Allloadsareappliedslowlyandgraduallyuntiltheyreachtothefull

magnitude and after reaching the full magnitude, the loads remain

constant.Thereby,neglectingimpact,inertial,anddampingforces.

3.ThematerialsappliedtothecomponentssatisfytheHooke’slaw.

4.Thechangeinstiffnessduetoloadingisneglected.

5.Boundaryconditionsdonotvaryduringtheapplicationofloads.Loads

mustbeconstantinmagnitude,direction,anddistribution.

GeometryAssumptions1.ThepartmodelmustrepresenttherequiredCADgeometry.

2.Onlytheinternalfilletsintheareaofinterestwillbeincludedin

thestudy.

3.Shellsarecreatedwhenthicknessofthepartissmallincomparisonto

itswidthandlength.

4.Thicknessoftheshellisassumedtobeconstant.

5. If the dimensions of a particular part are not critical and do not

affecttheanalysisresults,someapproximationscanbemadeinmodeling

theparticularpart.

6. Primary members of structure are long and thin like a beam then

idealizationisrequired.

7.Localbehavioratthejointsofbeamsorotherdiscontinuitiesarenot

ofprimaryinterestsonospecialmodelingoftheseareaisrequired.

8. Decorative or external features will be assumed insignificant to the

stiffness and the performance of the part and will be omitted from the

model.

MaterialAssumptions

1. Material remain in the linear regime. It is understood that either

stresslevelsexceedingyieldorexcessivedisplacementswillconstitutea

componentfailure.Thatisnonlinearbehaviorcannotbeaccepted.

2.Nominalmaterialpropertiesadequatelyrepresentthephysicalsystem.

3.Materialpropertiesarenotaffectedbyloadrate.

4. Material properties can be assumed isotropic (Orthotropic) and

homogeneous.

5.Partisfreeofvoidsorsurfaceimperfectionsthatcanproducestress

risersandskewlocalresults.

6. Actual non linear behavior of the system can be extrapolated from the

linearmaterialresults.

7.Weldmaterialandtheheataffectedzonewillbeassumedtohavesame

materialpropertiesasthebasematerial.

8.Temperaturevariationsmayhaveasignificantimpactontheproperties

ofthematerialsused.Changeinmaterialpropertiesisneglected.

BoundaryConditionsAssumptions1.ChoosingproperBC’srequireexperience.

2. Using BC’s to represent parts and effects that are not or cannot be

modeled leads to the assumption that the effects of these un-modeled

entities can truly be simulated or has no effect on the model being

analyzed.

3. For a given situation, there would be many ways of applying boundary

conditions.Butthesevariousalternativescanbewrongiftheuserdoes

notunderstandtheassumptionstheyrepresent.

4.Symmetry/anti-symmetry/reflectivesymmetry/cyclicsymmetryconditions

ifexistscanbeusedtominimizethemodelsizeandcomplexity.

5.Displacementsmaybelowerthantheywouldbeiftheboundaryconditions

beingmoreappropriate.Stressmagnitudesmaybehigherorlowerdepending

ontheconstraintused.

FastenersAssumptions1.Residualstressduetofabrication,pre-loadingofbolts,weldingand/or

othermanufacturingorassemblyprocessesareneglected.

2.Boltloadingisprimarilyaxialinnature.

3.Boltheadorwashersurfacetorqueloadingisprimarilyaxialinnature.

4.Surfacetorqueloadingduetofrictionwillproduceonlylocaleffects.

5. Bolts, spot welds, welds, rivets, and/or fasteners which connect two

componentsareconsideredperfectandactsasrigidjoint.

6.Stressrelaxationoffastenersorotherassemblycomponentswillnotbe

considered.Loadonthreadedportionofthepartisevenlydistributedon

engagedthreads

7.Failureoffastenerswillnotbereflectedintheanalysis.

GeneralAssumptions1. If the results in the particular area are of interest, then mesh

convergencewillbelimitedtothisarea.

2.Noslippagebetweeninterfacingcomponentswillbeassumed.

3.Anyslidingcontactinterfaceswillbeassumedfrictionless.

4. System damping will be normally small and assumed constant across all

frequencies of interest unless otherwise available from published

literatureoractualtests.

5.Stiffnessofbearingsinradialoraxialdirectionswillbeconsidered

infinite.

6. Elements with poor or less than optimal geometry are only allowed in

areasthatarenotofconcernanddonotaffecttheoverallperformanceof

themodel.

When a system under load is analyzed with linear static analysis, the

linear finite element equilibrium equations are solved to calculate the

displacementcomponentsatallnodes.Theseresultsareusedtocalculate

the strained components. These strain results along with stress-strain

relationshiphelpstocalculatestresses.

The procedure given next is generic and can be applied on any model and

assembly. But, we will use a model to help you understand the complete

procedurewithrealworldproblems.

PERFORMINGSTATICANALYSISProblem:Wehaveacomponentwhichisfixedbyitsroundbossfeatureandloadof

980N(100kgfapprox)isappliedontheitsflattop;refertoFigure-1.

We need to find out the Factor of Safety of the model and make it

optimized.

Figure-1.Problemofstaticanalysis

Toperformthestaticanalysisonanymodel,makesurethatyouhaveopened

themodelfileinSolidWorks.Thefileusedinthisexamplecanbefoundin

the resource kit for this book. After opening the file follow the steps

givennext.

StartingtheStaticAnalysis•Openthepartonwhichyouwanttoperformtheanalysis.

•ClickontheSolidWorksSimulationbuttonfromtheSOLIDWORKSAdd-Instab of theRibbon to add Simulation tab in the Ribbon, if not addedalready.

•ClickontheDownarrowbelowtheStudyAdvisorbuttonandselecttheNewStudy tool from the drop-down. Refer to Figure-2. List of analysis

studiesthatcanbeperformed,willbedisplayed.

Figure-2.StartingAnalysis

• Click on the Static button if not selected. Specify the name of the

analysisintheeditboxdisplayedabovethelistofanalyses.

•ClickontheOKbuttonfromthePropertyManager.Static 1 tab will beaddedatthebottomofthemodelingareaintheStudyBar.Also,thetoolsrelatedtotheanalysiswillbedisplayedintheRibbon;refertoFigure-3.

Figure-3.Analysisenvironment

ApplyingMaterial•ClickontheApplyMaterialbuttonfromthePropertyManager.TheMaterialdialogboxwillbedisplayed;refertoFigure-4.


•SelecttheCastAlloySteelfromtheleftareaofthedialogboxandselecttheApplybuttontoapplythematerial.

•ClickontheClosebuttontoclosethedialogbox.

ApplyingFixtures•ClickonthedownarrowbelowFixturesAdvisorintheRibbon.Thetoolsrelatedtofixtureswillbedisplayed;refertoFigure-5.

Figure-5.FixturesAdvisor

• Click on the Fixed Geometry button from the tool list. The FixturePropertyManagerwillbedisplayed;refertoFigure-6.


•Selecttheroundfaceofthemodeltomakeitfixed;refertoFigure-7.

Figure-7.Fixedgeometry

•ClickontheOKbuttonfromthePropertyManagertofixtheroundface.

Now, we need to specify the loads that are actually occurring on the

component.

ApplyingLoads• Click on the down arrow below External Loads Advisor button in the

Ribbon.Listofthetoolsrelatedtoloadswillbedisplayed;refertoFigure-8.

Figure-8.Externalloadsadvisor

•ClickontheForcebuttonfromthelist.TheForce/TorquePropertyManagerwillbedisplayedasshowninFigure-9.


•SelectthefaceasshowninFigure-10toapplytheforceload.

Figure-10.Faceselectedforapplyingload

•ClickintheForceValueboxinthePropertyManagerorinthemodelingarea and enter the value as 980 which is equal to 100 Kilograms of

weight. Refer to Figure-11. Note that you can change the unit of force

fromtheUnitdrop-downtoenter100kgfor220lbf.

Figure-11.Valuespecifiedforload

•ClickontheOKbuttonfromtheForce/TorquePropertyManager.Theforcewillbeappliedontheselectedface.

Forthisparticularproblem,wedonotrequireanyconnectiontobeapplied

sincethisisnotanassembly.Now,wearereadytodividethemodelinto

smallelementswiththehelpofmeshing.

MeshingthemodelNotethatyoucanskipthisstepifyoudonotwanttoexplicitlydefine

the element size for mesh. While running the analysis, system will

automatically create the suitable mesh for you. To explicitly define the

sizeofmeshelements,followthestepsgivennext.

•ClickonthedownarrowbelowtheRunbuttonintheRibbon.Thelistoftoolswillbedisplayed;refertoFigure-12.

Figure-12.CreateMeshtool

•ClickontheCreateMeshtoolfromthelist.TheMeshPropertyManagerwillbedisplayed;refertoFigure-13.

•ClickontheMeshParameterscheckbox.Therolloutwillexpandandtheoptionsrelatedtoelementsizeandtolerancewillbedisplayed;referto

Figure-14.


Figure-14.MeshParameters

•Setthedesiredvaluesintheparameterboxesintherolloutandclickon

theOK button from the PropertyManager. Note that the smaller value

given in the boxes will make the analysis slower because of more

calculations.ThemeshedmodelwillbedisplayedasinFigure-15.

Figure-15.Meshedmodel

•Tochangethemeshingforaparticularareaofthemodel,right-clickon

theMesh node in the Analysis Manager displayed at the left of the

modelingarea.Ashortcutmenuwillbedisplayed;refertoFigure-16.

•ClickontheApplyMeshControlbutton.TheMeshControlPropertyManagerwillbedisplayedasshowninFigure-17.

Figure-16.Meshingsimplification

Figure-17.MeshControlPropertyManager

• Select the faces of the model for which you want to change the mesh

elementssizes;refertoFigure-18.

Figure-18.Facesforchangingmeshsize

•MovethesliderintheMeshDensityrollouttowardscoarseorfineasperyour requirement. In this case, the selected area will be facing more

stressandweareconcernedmoreaboutthisarea.So,wewillmakefine

meshattheselectedfaceswithelementsizeof1.2mm.

•ClickontheOKbuttonfromthePropertyManagertocreatetheupdatedmesh.Notethatincreasingordecreasingtheelementsizewillalsoaffect

theaccuracyofresults.Decreasingtheelementsizegivesmoreaccurate

resultsbuttakemoreprocessing.

RunningtheAnalysis•ClickontheRunbuttonfromtheRibbon.Thesystemwillstartsolvingtheanalysis.

• After the processing is complete, the result of analysis will be

displayed;refertoFigure-19.

Figure-19.Analysisresult

• By default, results related to stress (vonMises) are displayed in the

modelingarea.

• To check Displacement and Strain related results, double-click on the

respectiveoptionfromtheAnalysisManagerintheleft.

Results(FactorofSafety)• To check results other than the default displayed, right-click on the

ResultsnodefromtheAnalysisManager.Ashortcutmenuwillbedisplayed;

refertoFigure-20.

• Click on theDefine Factor Of Safety Plot option to display the resultsrelated toFactorOf Safety. TheFactor of Safety PropertyManager will bedisplayedasshowninFigure-21.

Figure-20.Shortcutmenuforresults

Figure-21.FactorofSafetyPropertyManager

•Ifyouhaveaspecialcriteriaforcheckingsafetyfactorthenselectthe

respectiveoptionfromtheCriteriondrop-downintheStep1of3rolloutotherwise system will check the material properties and automatically

decidethebestcriteria.

•ClickontheOKbuttonfromthePropertyManager.TheFactorofSafetyplotwillbedisplayedinthemodelingarea;refertoFigure-22.

Figure-22.FactorofSafetyplot

Optimizingproduct•Ifyoucheckintheresultsdisplayedabovethemodel,theFactorofsafetydistributionMinFOS=0.7isdisplayedwhichshowsthatthemodelisnotsafeatthelocationsdisplayedindarkredcolor.Notethatforobjectto

besafeforloading,theFOSshouldbeabove1.•Here,weneedtoeitherchangethematerialorincreasethethicknessof

theobjecttosustaintheappliedload.

•Inthiscase,wechangethematerialtoAlloySteel.Todoso,right-clickon theMaterial node in theAnalysis Manager. A shortcut menu will bedisplayedasshowninFigure-23.

•SelecttheApply/EditMaterialfromthemenu.TheMaterialdialogboxwillbedisplayed.

•SelecttheAlloySteelmaterialfromthelefttableandclickontheApplybuttontoapplythematerial.

•ClickontheClosebuttonfromthedialogboxtocloseit.

Figure-23.Shortcutmenuformaterial

•Sincethematerialischanged,weneedtoruntheanalysisagain.Todo

so,clickontheRun button from theRibbon. The analysis will re-runandresultswillbedisplayed.

• Double-click on the Factor of Safety1 (-FOS-) node from the AnalysisManager.TheresultswillbedisplayedasshowninFigure-24.

Figure-24.UpdatedFactorofSafetyresults

•Now,thefactorofsafetyis2.5i.e.above1.So,ourproductcansustaintheappliedload.

SHELLMANAGERYoucanmanagealltheshells/surfacesatasingleplacebyusingtheShellManager. Shells are generally used to represent parts that have low

thickness like sheetmetal parts. The advantage of using shells lies in

element type used for them during meshing. For solid objects 3D elements

are used but for shells 2D elements like linear triangular and parabolic

triangularelementsareused.Theanalysisperformedusing2Delementsis

faster.TheproceduretousetheShellManagerisgivennext.

• Before using ShellManager, you should have a surface model; refer toFigure-25. This model is a representation of sheet metal part with

thicknessof3mmatthetopcurvedfaceand5mmontheotherfaces.

Figure-25.Surfacemodel

•Toassignthicknesstothemodel,clickontheShellManager tool fromthe Simulation CommandManager of the Ribbon. The Shell ManagerPropertyManager will be displayed with Shell Manager pane; refer to

Figure-26.

Figure-26.ShellManager

• If the object has uniform thickness then click in the cell under

ThicknesscolumnintheShellManagerpaneandenterthedesiredthicknessvalue; refer to Figure-27. Make sure that you have selected right unit

fromtheUnitcolumninthepane.

Figure-27.Uniformthicknessapplied

•Ifyouwanttospecifydifferentthicknesstodifferentfacesthenclick

intheselectionboxinPropertiesrolloutoftheShellManagerandselect

thefaces;refertoFigure-28.

Figure-28.SelectionboxinPropertiesrollout

•ClickontheOKbuttonfromtheShellManager.Awarningmessagewillbedisplayed. Click onYes to apply new selection of faces for shell. ThefaceswillbedisplayedintheShellManagerpane;refertoFigure-29.

Figure-29.ShellManagerpane

•Onebyone,enterthedesiredsheetthicknessforeachface.Makesure

thatyoupressENTERafterspecifyingthicknessinthecells.• Similarly, you can select other parameters like material, offset type

etc. for individual faces. Figure-30 shows the faces assigned with

differentmaterials.

Figure-30.Faceswithdifferentmaterialandthickness

•Afterspecifyingtheparameters,clickontheOKbuttonfromtheShellManager.Now,youcancontinuewiththeanalysisjustlikeasolidpart(withhybridmaterial).

PERFORMINGSTATICANALYSISUSINGSTUDYADVISOR

Earlierinthischapter,wehaveperformedthestaticanalysisbyselecting

eachoftherequiredoptionfromthelistoftoolsintheRibbon.Wecanuse the Study Advisor to perform all the steps related to analysis. ThestepstousetheStudyAdvisoraregivennext.

StartingtheStaticAnalysis•Openthepartonwhichyouwanttoperformtheanalysis.


• Click on the Down arrow below the Study Advisor button and select theStudyAdvisor tool from the drop-down. The study page of theSimulationAdvisorwillbedisplayedasshowninFigure-31.

Figure-31.StudypageofSimulationAdvisor

• Currently, we are planning to perform the stress analysis. For that,

click on the I am concerned about excessive deformation or stresses linkbutton. The second page of Study will be displayed in the SimulationAdvisor;refertoFigure-32.

Figure-32.SecondpageStudy

•Usingtheoptionsinthispage,wecancheckthedeformationplotforthe

present analysis. Deformation plot displays the visualization of

deformationfortheanalysis.

1. If you want to check the deformation for a specific

part/face/edge/vertexthenclickontheIneedtolimitdeformationinspecifiedregions of my model(parts, faces, edges, vertices) link button. The SensorPropertyManagerwillbedisplayedasshowninFigure-33.

Figure-33.SensorPropertyManager

2. Select the part/face/edge/vertex for which you want to check the

deformation; refer to Figure-34 and click on the OK button from the

PropertyManager.ThepagerelatedtomaterialfailurewillbedisplayedintheSimulationAdvisor.

Figure-34.Faceselectedfordeformationtesting

•IfyouwanttospecifylimitfordeformationthenclickontheNothinginmy design may deform more than a specified amount. The SensorPropertyManagerwillbedisplayed.

1.ClickontheAlertrollouttoexpandit.TheoptionsintherolloutwillbedisplayedasshowninFigure-35.

2. Click in the edit box and specify the limit of deformation. If the

deformationcrossesthespecifiedvaluethenanalertwillbedisplayed.

3. ClickOK button from the PropertyManager. Page related to materialfailurewillbedisplayedintheSimulationAdvisor;refertoFigure-36.

Figure-35.SensorPropertyManagerwithAlertoptions

Figure-36.SimulationAdvisorwithpagerelatedtomaterialfailure

• Click on the I want to check material failure link button to check for

materialfailure.Thenextpageformaterialfailurewillbedisplayedin

theSimulationAdvisor;refertoFigure-37.

•ClickontheIdon’tknowwheretoexpectfailure.Checkthewholemodellinkbuttontocheckthewholemodelformaterialfailure.YoucanselecttheIammostconcernedaboutfailureatspecificlocationsinmymodellinkbuttonifyou want to check the material failure for a specific portion. In this

case, we have selected the first link button. On doing so, again the

SensorPropertyManagerisdisplayedwhereyoucanspecifythealertformaximum stress. Note that the maximum bearable stress is generally

obtainedbymaterialproperties.

•ClickontheOKbuttonfromthePropertyManagerandthenclickontheNextlinkbuttonfromtheSimulationAdvisor,thenameofthestudythatsuitsyourrequirementswillbedisplayed;refertoFigure-38.

Figure-37.SimulationAdvisorwithanotherpagerelatedtomaterialfailure

Figure-38.SimulationAdvisorwithStudyname

•ClickontheCreateaStaticStudylinkbuttonandthenclickontheNextlinkbuttonfromtheSimulationAdvisor.TheBodiesandMaterialpagewill

bedisplayedintheSimulationAdvisor.

• Click on the Next button from the pages related to symmetry will be

displayed; refer to Figure-39. Note that if you apply symmetry then

calculationtimeforanalysiswillbereduced.

Figure-39.SimulationAdvisorwithsymmetrypage

• Click on the desired link from the SimulationAdvisor. For the currentexample, click on theMirrored link button and then click on theAddsymmetry fixtureonsolid faceslinkbuttonfromtheSimulationAdvisor. TheFixturePropertyManagerwillbedisplayed;refertoFigure-40.

•Youcanapplythesymmetryoptionasdiscussedinpreviouschapter.

•AfteryouarefinishedwiththesymmetrythenclickontheFinishedwithSymmetrylinkbutton.Thepagerelatedtobodysetupwillbedisplayed;refertoFigure-41.

Figure-40.FixturePropertyManagerwithsymmetryoption

Figure-41.Pagerelatedtobodysetup

• Click on theChange body setup link button to specify setting for thebody.Youaredisplayedamessageboxsayingthatyouneedtoright-click

onthebodyandselecttheTreatasoption.Right-clickonthenameofthemodel in theAnalysis Manager and select the desired treat as option;refer to Figure-42. The options related to the selected option will be

displayedintheformofPropertyManager.Actaccordingly.

• Now, click on theNext button from the body setup page of SimulationAdvisor.Thematerialpagewillbedisplayed;refertoFigure-43.

Figure-42.Treatasoptions

Figure-43.MaterialpageofSimulationAdvisor

•ClickontheChoosemateriallinkbuttontospecifythematerialforthecurrent model. TheMaterial dialog box will be displayed as discussed

earlier.Selectthematerial,clickontheApplybuttonandthenclickon

theClosebutton.TheappliedmaterialwillbedisplayedintheSimulationAdvisor.

•ClickontheNextbuttonfromtheSimulationAdvisor.TheInteractionspagewillbedisplayed;refertoFigure-44.

Figure-44.SimulationAdvisorwithInteractionpage

Now onwards, the path of usingSimulationAdvisor becomes very confusing.So,wewillgobacktoRibbonandselectthedesiredoptionfromthere.

•ClickontheFixturesAdvisorbuttonfromtheRibbon.TheoptionsrelatedtofixtureswillbedisplayedintheSimulationAdvisor;refertoFigure-45.

•ClickontheAddafixturelinkbutton.TheFixturePropertyManagerwillbedisplayedasdiscussedearlier.

• Select the bottom face of the current model; refer to Figure-46. And

clickontheOKbuttonfromthePropertyManagertoapplythefixture.

Figure-45.OptionsforfixtureinSimulationAdvisor

Figure-46.Faceselectedforfixture

• Click on theExternal Loads Advisor button from theRibbon. The loadspageofSimulationAdvisorwillbedisplayed;refertoFigure-47.

Figure-47.LoadspageofSimulationAdvisor

• Click on theAdd a load link button. The Force/Torque PropertyManagerwillbedisplayedasdiscussedearlier.

•Selectthetopfaceofthemodelandspecifythevalueofforceas392N;refertoFigure-48.


• Click on theDone -Continue to nextAdvisor section link button from theSimulationAdvisor. TheMesh andRun page ofSimulationAdvisor will bedisplayedasshowninFigure-49.

Figure-48.Forceappliedontopface

Figure-49.MeshandRunpage

•ClickontheChangesettingslinkbuttonandthenspecifythedesiredmeshsizesforglobalorlocalareasofthemodel.

•Inourcase,weusethedefaultsettingsandclickontheRunTheStudylinkbutton.Firstmeshingwillbeprocessesandthentheanalysiswillbe

performed.Aftertheanalysisiscompleted,thentheresultspagewillbe

displayedintheSimulationAdvisorasshowninFigure-50.

•ClickonthePlaybuttonfromtheSimulationAdvisortochecktheresults.ClickontheStopbuttontostopanimation.

• Click on theEverything looks reasonable link button to check the otherresults.

•Next,ClickontheMaterialbreakingoryieldinglinkbuttonandthenShowFactor of Safety plot link button to plot theFactor of Safety result. Theresultwillbedisplayed;refertoFigure-51.

Figure-50.ResultpageofSimulationAdvisor

Figure-51.Factorofsafetyresult

•ClickontheSuggestionstoimprovedesignlinkbuttonandyouwillgettoknowthemethodstoincreasestrengthoftheproductifrequired;referto

Figure-52.

Figure-52.Suggestionstoimprovestrength

•Bydefault,theVon-misesstressplotisdisplayedbutsometimesweneed

otherplotsofstressalso.Todoso,right-clickontheResultsnodeintheAnalysisManager and select theDefine Stress Plot option. The StressPlotPropertyManagerwillbedisplayed;refertoFigure-53.

Figure-53.StressPlotPropertyManager

•ClickontheComponent drop-down and select theP1: 1st Principal Stressoptionfromthelistdisplayed.

• Click on the OK button from the PropertyManager. The plot will be

created.

STATICANALYSISONASSEMBLYProblem:WehaveanassemblyofwallbracketasshowninFigure-54.Thebracketis

boltedtovirtualwallwiththehelpoffoundationbolts.Loadof100kgis

appliedattheflatendofthesupport.Checkthecomponent/componentsthat

are failing in the static analysis. The part files are available in the

resourcesofthisbook.

Figure-54.Assemblyofwallbracketforstaticanalysis

UnderstandingProblem:In this case, we have an assembly of three components connected to each-

other. The base plate is attached to a virtual wall with the help of

foundationbolts.Thearmisconnectedtobasewiththehelpofapin.Now,

wewillapplytheseconditionsinSolidWorksSimulation.

StartingAnalysis• Open the assembly file of model on which you want to perform the

analysis.


•ClickontheDownarrowbelowtheStudyAdvisorbuttonandselecttheNewStudy tool from the drop-down. List of analysis studies that can be

performed,willbedisplayed.

• Click on the Static button if not selected. Specify the name of the

analysisintheeditboxdisplayedabovethelistofanalyses.

•ClickontheOKbuttonfromthePropertyManager.Static 1 tab will beaddedatthebottomofthemodelingareaintheStudyBar.Also,thetoolsrelatedtotheanalysiswillbedisplayedintheRibbon.

ApplyingMaterialtoPartsofAssemblyThere are two ways to apply material to the parts of assembly; Applying

same material to all the components and applying different materials to

componentsoftheassembly.Wewillbeapplyingdifferentmaterialtothe

assemblycomponents.

•Right-clickontheBasecomponentfromthePartscategoryintheAnalysisManager.Ashortcutmenuwillbedisplayed;refertoFigure-55.

Figure-55.Shortcutmenupartsofassembly

• Click on the Apply/Edit Material option from the shortcut menu. The

Materialdialogboxwillbedisplayed.

•SelecttheCastAlloySteelfromtheleftareaofthedialogboxandclickon theApply button. Click on theClose button from the dialog box toexit.

•Similarly,applyalloysteeltoarmandstud.

Note that you want to apply same material to all the components in the

assembly then right-click on the Parts category and click on the ApplyMaterialtoAlloptionfromtheshortcutmenudisplayed;refertoFigure-56.

Figure-56.ApplyMaterialtoAlloption

SettingGlobalContactsBydefault, SolidWorks Simulation applies bonded contacts between all the

components in the assembly which means all the components are perfectly

bonded and behave as if they are single model entity. But we need a no

penetration contact in which all the components of assembly are separate

and make affect on each other due to load applied. The procedure is

discussednext.

• Expand theComponentContacts sub-category in theConnections categoryintheAnalysisManager;refertoFigure-57.

• Right-click on theGlobal Contact option and select the Edit Definitionoption from the shortcut menu displayed. The Component ContactPropertyManagerwillbedisplayedasshowninFigure-58.

Figure-57.Expandedcomponentcontactssub-category

Figure-58.ComponentContactPropertyManagerforassembly

•SelecttheNoPenetrationradiobuttonfromtheContact Type rollout inthePropertyManager.

•ClickontheOKbuttonfromthePropertyManagertoexit.

SettingContactManuallyThis section is just for information and does not affect the results of

currentanalysis.Youcanskipthissectionifyouwishto.

•ClickontheContactSettoolfromtheConnectionsAdvisordrop-downintheRibbon. The Contact Sets PropertyManager will be displayed; refer to

Figure-59.

• Select the Automatically find contact sets radio button from the

PropertyManager and select theTouching faces radio button to highlightallthecontactsthatarecreatedbycontactsofassemblyparts.

•Onebyoneselectallthecomponentsofassemblyforwhichyouwantto

createthecontactsets;refertoFigure-60.

Figure-59.ContactSetsPropertyManagerforassemblycomponents

Figure-60.Componentsofassemblyselected

• Click on the Find contact sets button in the Components rollout. The

contactsetswillbedisplayedinResultsrollout.

•SelectthecontactsetandsetthedesiredconditionintheTypedrop-down.

• After setting all the contacts, click on the OK button from the

PropertyManagertoexit.

CreatingVirtualWallAsthenamesuggests,virtualwallactsasavirtualwallfortheassembly.

Wewilluseitlatertofastenfoundationbolts.

•ClickontheContactSetstoolfromtheConnectionsAdvisor drop-down intheRibbon.TheContactSetsPropertyManagerwillbedisplayed.

•SelectVirtualWalloptionfromtheTypedrop-downintheTyperolloutofthePropertyManager;refertoFigure-61.

Figure-61.VirtualWalloption

•SelecttheflatbackfaceofthebasepartandthenclickintheTargetPlaneselectionbox;refertoFigure-62.

Figure-62.Faceselectedforvirtualwall

•ExpandthedesigntreefromviewportandselecttheFrontplaneofBase

part;refertoFigure-63.

Figure-63.Planeselectedforvirtualwall


CreatingFoundationBoltconnectionFoundationboltsgiveusthebenefitoffixinganyobjecttothewall/floor

usingbolts.Theproceduretocreateconnectionisgivennext.

• Click on the Bolt tool from the Connections Advisor drop-down in the

Ribbon. The Connectors PropertyManager will be displayed with the

optionsrelatedtobolts.

•SelecttheFoundationBoltbuttonfromtheTyperollout;refertoFigure-64.

Figure-64.FoundationBoltbutton

•Selecttheroundedgeofaholeinthebaseplate;refertoFigure-65.

Figure-65.Edgeselectedforfoundationbolt

•ClickintheTargetPlaneselectionboxinthePropertyManagerandselecttheFrontplaneofbasepartusingtheDesignTreeinviewport.

• Move downward inPropertyManager and set the Torque value of pre-load600N.m.

• Click on theOK button from thePropertyManager. The foundation boltwillbecreated.

•Similarly,createthefoundationboltsforotherholesofbase.

ApplyingLoad•ClickontheForcetoolfromtheExternalLoadsAdvisordrop-downintheRibbon.TheForce/TorquePropertyManagerwillbedisplayed.

•SelecttheflatfaceoftheArmpartandselecttheMetric option fromtheUnitdrop-downinthePropertyManager;refertoFigure-66.

Figure-66.Faceselectedforload

• Specify the value of load as 100 in the Force value edit box in

PropertyManager.


Meshing•ClickontheCreateMeshtoolfromtheRundrop-downintheRibbon.TheMeshPropertyManagerwillbedisplayed.

•MovetheMeshDensityslidertowardsCoarse;refertoFigure-67andclickontheOKbuttontocreatemeshing.Thiswillreducetheprocessingtime

of analysis but reduce the accuracy also. If you have good system

configurationandyouareveryseriousaboutresultsofthisanalysisthen

movetheslidertowardsFine.

Figure-67.MeshPropertyManagerwithCoarsedensity

RunningAnalysisBefore running analysis, we need to select the Direct Sparse solver for

solving analysis because we have used the No penetration contact in our

analysis.Theuseofdifferentsolversisdiscussednext.

AutomaticThesoftwareselectsthesolverbasedonthestudytype,analysisoptions,

contactconditions,etc.Someoptionsandconditionsapplyonlytoeither

DirectSparseorFFEPlus.

DirectSparseSelecttheDirectSparse:•whenyouhaveenoughRAMandmultipleCPUsonyourmachine.

•whensolvingmodelswithNoPenetrationcontact.

•whensolvingmodelsofpartswithwidelydifferentmaterialproperties.

Forevery200,000dof,youneed1GbofRAMforlinearstaticanalysis.The

DirectSparsesolverrequires10timesmoreRAMthantheFFEPlussolver.

FFEPlus(iterative)TheFFEPlussolverusesadvancedmatrixreorderingtechniquesthatmakesit

moreefficientforlargeproblems.Ingeneral,FFEPlusisfasterinsolving

largeproblemsanditbecomesmoreefficientastheproblemgetslarger.

Forevery2,000,000dof,youneed1GbofRAM.

LargeProblemDirectSparseBy leveraging enhanced memory-allocation algorithms, the Large Problem

Direct Sparse solver can handle simulation problems that exceed the

physicalmemoryofyourcomputer.

IfyouinitiallyselecttheDirectSparsesolverandduetolimitedmemory

resourcesithasreachedanout-of-coresolution,awarningmessagealerts

youtoswitchtotheLargeProblemDirectSparse.

The Large Problem Direct Sparse (LPDS) solver is more efficient than the

FFEPlusandDirectSparsesolversattakingadvantageofmultiplecores.

IntelDirectSparseTheIntelDirectSparsesolverisavailableforstatic,thermal,frequency,

lineardynamic,andnonlinearstudies.

By leveraging enhanced memory-allocation algorithms and multi-core

processing capability, the Intel Direct Sparse solver improves solution

speedsforsimulationproblemsthataresolvedin-core.

ProceduretoselectDirectsparsesolverisgivennext.

• Right-click on the analysis name inAnalysis Manager. A shortcut menuwillbedisplayed;refertoFigure-68.

Figure-68.Shortcutmenuforpropertiesofanalysis

•ClickonthePropertiesoptionfromtheshortcutmenu.TheStatic dialogboxwillbedisplayedwithpropertiesofanalysis.

•SelecttheDirectsparsesolveroptionfromthedrop-downintheSolverareaofthedialogbox;refertoFigure-69.

Figure-69.Directsparsesolveroption

•ClickontheOKbuttonfromthedialogbox.

Now,wearereadytoruntheanalysis.

•ClickontheRunbuttonfromtheRibbonandchecktheresults.Youwillgetlargedisplacementintheanalysis.Thisisthestagewhereweneedto

changethedesiredmodeltosustaintheload.

Onesolutiontothisproblemcanbeaddingribtothebasepartasshownin

Figure-70.Thechangedbasepartisalsoavailableintheresourceforthe

book.Replaceitwiththebasepartinassemblyandre-runtheanalysisto

seethemagic.

Figure-70.Changedbasepart

ADAPTIVEMESHINGThere are three type of meshing available in SolidWorks Simulation;

StandardMeshing, h-adaptive meshing, and p-adaptive meshing. Most of the

time,thestandardmeshingdoestheworkinstaticanalyses.But,whenwe

needmoreaccurateresultsaredeformingareathenweuseh-adaptiveorp-

adaptivemeshingschemes.Moredetailonh-adaptiveandp-adaptiveisgiven

next.

h-AdaptiveMeshingInh-adaptivemeshing,systemsolvestheanalysisbyusingstandardmeshing

and then system solves the analysis again with a refined mesh at the

locations of strain. This process continues up to the number of steps

definedbyusortillthedesiredaccuracyisachievedfromtheanalysis.

Thisrepetitionofanalysisincreasestheprocessingtimesothistypeof

meshing is suggested when you are concerned about high accuracy. The

proceduretoapplyh-adaptivemeshinginthestaticstudyisgivennext.

• After starting the Static study in SolidWorks Simulation, click on theStudyPropertiestoolfromtheStudyAdvisordrop-downintheRibbon.The

StaticdialogboxwillbedisplayedasshowninFigure-71.

Figure-71.Staticdialogbox

• Click on theAdaptive tab from the dialog box. The options related toadaptivemeshingwillbedisplayed;refertoFigure-72.

Figure-72.Partialviewofadaptiveoptions

•Clickontheh-adaptiveradiobuttonfromtheAdaptivemethodareaofthedialogbox.Theoptionsrelatedtoh-adaptivemeshingwillbecomeactive;

refertoFigure-73.

Figure-73.h-adaptiveoptions

•SetthetargetaccuracybyusingthesliderforTargetaccuracy.

• Set the accuracy bias using the Accuracy bias slider. If you want toconcentrateonareaunderhigherstressthenmovetheslidertowardsleft

i.e.Local(Faster).Ifyouwanttoincreaseaccuracyforthewholemodelthenmovetheslidertowardsrighti.e.Global(Slower).

•SetthenumberofloopsintheMaximumno.of loopsspinnertosetthenumberoftimesanalysisshouldrunforaccuracy.

•SelecttheMeshcoarseningcheckboxtomakemeshingcoarseintheareaswhichareofnointerest.

•ClickontheOKbuttonfromthedialogboxandruntheanalysistocheck

thedifferenceinmeshingandresults.Figure-74showsonsuchexample.

Note that if the specified accuracy is not reached in number of loops

specifiedinthedialogboxtheneachtimeyouclickontheRunbuttontore-runthestudy,theresultswillbecomeaccuratefurthertillthedesired

accuracyisachievedincaseofh-adaptivemeshing.

Figure-74.Standardandh-adaptivemeshing

p-AdaptiveMeshingInh-adaptivemeshing,wehaveseenthatsizeofthemeshelementreduces

and number of elements increase in the area of interest. In p-Adaptive

meshing, the order of mesh element changes. We have earlier discussed in

this book that SolidWorks Simulation provides beam element for linear

problems,triangularelementsfor2Dproblems,andtetrahedralelementsfor

3Dproblems.So,instandardmeshinghighestorderelementistetrahedral

butthisisnottrueifyouhaveselectedp-adaptivemeshing.Inthiscase,

theelementscanbefrominitial2ndordertomaximum5thorderdependingon

analysisrequirements.Theproceduretousethep-adaptivemeshingisgiven

next.

•Clickonthe p-adaptive radio button from the Adaptive tab in theStaticdialogboxdiscussedearlier.Theoptionswillbedisplayedasshownin

Figure-75.

Figure-75.p-Adaptiveoptions

•Setthestoppingconditionforpolynomialincrementofmeshelementsby

usingthedrop-downandeditboxinfirstlineofp-Adaptiveoptionsarea

of the dialog box. There are three options in the drop-down; RMS Res.

Displacement, RMS von Mises Stress, and Total Strain Energy. Select the

desiredoptionandsetthepercentagevalueofchangetobeachievedwhile

makingresultsaccurate.Ifthechangeinselectedparametersislessthan

thispercentagethenloopwillnotrunfurther.

•TheUpdateelementswithrelativeStrainEnergyerrorofeditboxisusedtospecifythemaximumallowederrorvalueintheStrainenergyresults.The

elementsthataregeneratingerrormorethanthisvaluewillbeupgraded.

• Specify the starting polynomial order and maximum polynomial order by

using the respective spinners in the dialog box. Note that minimum

polynomialordercanbe2andmaximumpolynomialordercanbe5.

• Specify the number of loops up to which the analysis should run for

accuracy.Themaximumnumberofloopscanbe4.

•Afterspecifyingtheparameters,clickontheOKbuttonfromthedialog

boxandruntheanalysis.

Figure-76 shows the example used for h-adaptive meshing solved by p-

adaptivemeshing.

Figure-76.p-adaptivemeshingresults

SUBMODELINGSTUDYWehaveworkedearlieronanassemblyofwallbracketandfoundthatthe

reason of failure was base of wall bracket for which we added ribs as

solution. But sometimes our components are hidden in the assembly and we

are not able to check the stress without explicitly running analysis on

them.Tosolvethisproblem,weuseSubmodelingstudy.InSubmodelingstudy

the selected portion of assembly is analyzed for the loads that are

applicableonitduringanalysisofwholeassembly.Inthisway,youdonot

requirecalculationsofremoteload.Notethatthisoptionisavailablefor

StaticandNon-linearstaticanalysesonly.

Submodeling is based on the St. Venant’s principle. The St. Venant’s

principlestatesthatthestressesonaboundaryreasonablydistantfroman

applied load are not significantly altered if this load is changed to a

statically equivalent load. The distribution of stress and strain is

alteredonlyneartheregionsofloadapplication.Youmaycutaportionof

themodel,refinethemesh,andrunanalysisonlyfortheselectedportion

providedthatdisplacementsareproperlyprescribedatthecutboundaries.

If displacement results from the parent study are accurate, then these

displacementsare considered as boundary conditions at the cut boundaries

for the submodeling study. So, may need to use adaptive meshing for

accurateresultsofdisplacement.Notethattheboundariesofthesubmodel

mustbeadequatelyfarfromstressconcentrationareas.

Thereareafewconditionstousesubmodelingstudylike,

•Thestudytypemustbestaticornonlinearstaticwithmorethanonebody

and not be a submodeling study itself. The parent study cannot be a 2D

Simplificationstudy.

• The selected bodies of the submodel cannot have No penetration contact

with unselected bodies that creates contact pressure across the cut

boundary.

• The selected bodies of the submodel cannot share connectors with

unselected bodies. For example, the piping assembly below is not a

suitable parent model. A submodel of two parts is connected to the

excludedthirdpartwithbolts.

•Thecutboundaryofthesubmodelcannotcutthroughbodies.

• The cut boundary of the submodel cannot cut through a bonded contact

definedbyeitherbeam-to-beamjointsorshelledge-to-shelledgejoints.

•Thebondedcontactatthecutboundaryofthesubmodelisformulatedwith

anincompatiblemesh.

The procedure to use submodeling study is discussed next through an

example.

WehaveperformedastaticanalysisonassemblygiveninFigure-77.Now,we

want to check the results for Part 2 more precisely. To do so, we will

createasubmodelingstudyforwhichthestepsaregivennext.

Figure-77.Assemblywithboundaryconditions

•Right-clickontheanalysisnameintheAnalysisManagerandclickontheCreateSubmodelingStudyoptionfromtheshortcutmenudisplayed;refertoFigure-78. The Submodeling Information dialog box will be displayed asshowninFigure-79.

Figure-78.CreateSubmodelingStudyoption

Figure-79.SubmodelingInformationdialogbox

•ClickontheOKbuttonfromthedialogbox.Youareaskedtoselectthe

bodiesthatyouwanttoincludeinsubmodelingstudy.

•Selectthecheckboxforthepartthatyouwanttoincludeinstudyfrom

theDefineSubmodelPropertyManager;refertoFigure-80.

Figure-80.DefineSubmodelPropertyManager

• Click on theOK button from thePropertyManager. All the un-selectedbodieswillbeexcludedfromthestudyandthestudyenvironmentwillbe


Figure-81.Submodelingstudyinterface

• Click on the Run This Study button from the Ribbon. The result of

assembly load will be displayed on the selected components; refer to

Figure-82.

Figure-82.Resultofsubmodelanalysis

LOADCASEMANAGERUsingLoadCaseManager,wecancreatedifferentcasesofloadingonthecomponent and we can simultaneously judge the results of component in

differentloadingconditions.Thisfeaturehelpsusfindoutthestability

ofcomponentinentirelydifferentconditions.Forexample,weneedtotest

a component in a high temperature environment of 80 degree Celsius and a

lowtemperatureenvironmentof-20degreeCelsiuswithdifferentloadsof

20tonneand15tonne(Ihopeyouknowdifferencebetweentonandtonne).

Todosuchanalyses,wefindloadcasemanagerveryhelpful.Notethatload

case manager is available for static analysis only and that too when p-

adaptiveandh-adaptivemeshingisnotselected.Now,wewilldiscussthe

useofloadcasemanagerwithanexample.

We have a static analysis performed on an alloy steel block; refer to

Figure-83.

Figure-83.Staticanalysiswithboundaryconditions

•Right-clickontheanalysisnameintheAnalysisManagerandselecttheLoad Case Manager option from the shortcut menu displayed; refer to

Figure-84.TheLoadCaseManagerwillbedisplayed;refertoFigure-85.

Figure-84.LoadCaseManageroption

Figure-85.LoadCaseManager

•ClickonthetogglebuttonsintheManagertodisplayorhidefixtures,

loads,andconnectors.

•Clickonthe+signunderPrimaryLoadCasesnode.Anewloadcasewill

beadded;refertoFigure-86.

Figure-86.Addingloadcase

•ClickonSuppressoptioninthefieldforwhichyouwanttospecifynewvalue.Adrop-downwillbedisplayed;refertoFigure-87.

Figure-87.Suppressoptionforloads

•Selecttheearlierspecifiedvaluefromthedrop-downandspecifythenew

valuelike80.

•Similarly,specifyvalueofotherloadsintherespectivefields.

•Afterspecifyingthevaluesofcase1,againclickonthe+signinthePrimary Load Case node and repeat the procedure to specify loads for

secondcase.

•YoucancombinevariousloadcasesbyusingtheLoadCaseCombinationsnodeoptions.Clickonthe+signunderLoadCaseCombinationsnode.TheEditEquation(LoadCaseCombination)dialogboxwillbedisplayed;refertoFigure-88.

Figure-88.EditEquation(LoadCaseCombination)dialogbox

•SetthedesiredloadingequationandclickontheOKbuttontocombine

variousloadingcases.

•Aftersettingthedesiredparameters,clickontheRunbuttonfromtheLoad Case Manager. The system will solve various cases and display

resultsinviewport.

•Tochecktheresultofaloadingcase,clickonitsnamefromResultsViewtabintheLoadCaseManager;refertoFigure-89.

Figure-89.Resultforloadcase

•ClickontheReportbuttontocreatereportforloadingcases.

•ClickontheClosebuttonatthetop-rightofLoadCaseManagertocloseit.

PRACTICE1

Considerarectangularplatewithcutout.Thedimensionsandtheboundary

conditionsoftheplateareshowninFigure-90.Itisfixedononeendand

loadedontheotherend.Underthegivenloadingandconstraints,plotthe

deformed shape. Also, determine the principal stresses and the von Mises

stressesinthebracket.Thicknessoftheplateis0.125inchandmaterial

isAISI1020.

Figure-90.DrawingforPractice1

PRACTICE2

Downloadthemodelforpractice2ofchapter3fromtheresourcekitand

performthestaticanalysisusingtheconditionsgiveninFigure-91. Find

outtheFactorofSafetyforthemodel.

Figure-91.Practice2

PRACTICE3

Downloadthemodelofchairinchapter3fromtheresourcekitandperform

thestaticanalysisusingtheconditionsgiveninFigure-92.Thematerial

used for manufacturing chair is PET (Polyethylene terephthalate). Check

whetheritissafe.Also,checkwhetherRikishi(wrestler)cansitonthis

chairwithoutanyconsequences.Hisweightis193Kg.

Figure-92.Practice3forStaticAnalysis

SELF-ASSESSMENT

Q1.Whichofthefollowingisnotanassumptionforstaticanalysis?

a.Theloadsapplieddoesnotvarywithtime.

b.Thechangeinstiffnessduetoloadingisneglected.

c.Materialpropertiesarenotaffectedbyloadrate.

d.Weldmaterialandtheheataffectedzonewillbeneglected.

Q2.Whichofthefollowingisnotanassumptionforstaticanalysis?

a.Residualstressduetofabrication,pre-loadingofbolts,weldingand/or

othermanufacturingorassemblyprocessesareneglected.

b.Boltloadingisprimarilyaxialinnature.

c.Failureoffastenerswillbereflectedintheanalysis.

d.Surfacetorqueloadingduetofrictionwillproduceonlylocaleffects.

Answerthefollowingquestionsincontextofgeneralanalysisassumptions:

Q3. If the results in the particular area are of interest, then mesh

convergenceshouldbelimitedtothisarea.(T/F)

Q4.Noslippagebetweeninterfacingcomponentswillbeassumed.(T/F)

Q5.Stiffnessofbearingsinradialoraxialdirectionswill

beconsideredinfinite.(T/F)

Q6.Whenasystemunderloadisanalyzedwithlinearstaticanalysis,the

linear finite element equilibrium equations are solved to calculate the

displacementcomponentsatallnodes.(T/F)

Q7.Forsolidobjects3Delementsareusedbutforshells2Delementslike

lineartriangularandparabolictriangularelementsareused.(T/F)

Q8.Youcanmanagealltheshellsatasingleplacebyusingthetoolfrom

Ribbon.

Q9. By default, SolidWorks Simulation applies …………. contacts between all

thecomponentsintheassembly.

Q10.……………boltsgiveusthebenefitoffixinganyobjecttothewall/floor

usingbolts.

Non-LinearStaticAnalysis

Chapter5

TopicsCovered


•Introduction

•StartingNon-LinearStaticAnalysis.


•DefiningFixtures

•Applyingloads




NONLINEARSTATICANALYSISAllrealstructuresbehavenonlinearlyinonewayoranotheratsomelevel

ofloading.Insomecases,linearanalysismaybeadequate.Inmanyother

cases, the linear solution can produce erroneous results because the

assumptionsuponwhichitisbasedareviolated.Nonlinearitycanbecaused

bythematerialbehavior,largedisplacements,andcontactconditions.

Youcanuseanonlinearstudytosolvealinearproblem.Theresultscanbe

slightlydifferentduetodifferentprocedures.

Innonlinearfiniteelementanalysis,amajorsourceofnonlinearityisdue

totheeffectoflargedisplacementsontheoverallgeometricconfiguration

of structures. Structures undergoing large displacements can have

significant changes in their geometry due to load-induced deformations

whichcancausethestructuretorespondnonlinearlyinastiffeningand/or

asofteningmanner.

Forexample,cable-likestructuresgenerallydisplayastiffeningbehavior

onincreasingtheappliedloadswhilearchesmayfirstexperiencesoftening

followed by stiffening, a behavior widely-known as the snap-through

buckling.

Another important source of nonlinearity stems from the nonlinear

relationship between the stress and strain which has been recognized in

several structural behaviors. Several factors can cause the material

behavior to be nonlinear. The dependency of the material stress-strain

relationontheloadhistory(asinplasticityproblems),loadduration(as

in creep analysis), and temperature (as in thermoplasticity) are some of

thesefactors.

This class of nonlinearity, known as material nonlinearity, can be

idealized to simulate such effects which are pertinent to different

applicationsthroughtheuseofconstitutiverelations.

Aspecialclassofnonlinearproblemsisconcernedwiththechangingnature

of the boundary conditions of the structures involved in the analysis

during motion. This situation is encountered in the analysis of contact

problems.

Pounding of structures, gear-tooth contacts, fitting problems, threaded

connections, and impact bodies are several examples requiring the

evaluationofthecontactboundaries.Theevaluationofcontactboundaries

(nodes,lines,orsurfaces)canbeachievedbyusinggap(contact)elements

betweennodesontheadjacentboundaries.

Yielding of beam-column connections during earthquakes is one of the

applicationsinwhichmaterialnonlinearityareplausible.

THEORYBEHINDNON-LINEARANALYSISAsyouhavelearntfromintroduction,therearethreefactorswhichcause

non-linearity in the body which are elastic behavior of material, large

displacementinbody,andvariationincontact.Intermsofequationthis

canbeexpressedas

[K(D)]{D}={F}

Here,K(D)isstiffnessmatrixwhichisfunctionofdisplacement.

Disthedisplacementmatrix

andFistheForceapplied

So,fromtheaboveequationyoucaneasilyunderstandthatthestiffnessis

changing according to the displacement. Note that displacement is vector

anditalsohasadirection.Ifwecomparethelinearstaticanalysisand

non-linear static analysis curves then we can find out the different

effectsofloadinbothconditions;refertoFigure-1.

Figure-1.StressStraindiagrams

Intermsofloadanddisplacement,thecurveforbothanalysiscanbegiven

byFigure-2.

Figure-2.Loaddisplacementcurve

The normal incremental iteration does not work good for the non-linear

analysis and generate errors as shown in Figure-3. So, Newton-Raphson

algorithmisusedtosolvethenon-linearequation.

Figure-3.Errorinincrementalinterativemethod

TheequationforNewton-Raphsonmethodisgivenas:

[KT]{Δu}={F}-{Fnr}

[KT]=tangentstiffnessmatrix

{Δu}=displacementincrement

{F}=externalloadvector

{Fnr}=internalforcevector

Theiterationcontinuestill{F}-{Fnr}(differencebetweenexternaland

internalloads)iswithinatolerance;refertoFigure-4.

Figure-4.Newton-Raphsonmethod

Thusanonlinearsolutiontypicallyinvolvesthefollowing:

• One or more load steps to apply the external loads and boundary

conditions.(Thisistrueoflinearanalysestoo.)

•Multiplesub-stepstoapplytheloadgradually.Eachsub-steprepresents

oneloadincrement.(Alinearanalysisneedsjustonesub-stepperload

step.)

• Equilibrium iterations to obtain equilibrium (or convergence) at each

sub-step.(Doesnotapplytolinearanalyses.)

RoleofTimeinNon-LinearAnalysisEach load step and sub-step is associated with a value of time. Time in

most nonlinear static analyses is simply used as a counter and does not

meanactual,chronologicaltime.Figure-5showsaload-timecurve.

Figure-5.Loadtimecurve

Bydefault,time=1.0attheendofloadstep1,2.0attheendofload

step 2, and so on. For rate-independent analyses, you can set it to any

desired value for convenience. For example, by setting time equal to the

loadmagnitude,youcaneasilyplottheload-deflectioncurve.

The“timeincrement”betweeneachsub-stepisthetimestepΔt.Timestep

ΔtdeterminestheloadincrementΔFoverasub-step.Thehigherthevalue

ofΔt,thelargertheΔF,soΔthasadirecteffectontheaccuracyofthe

solution.SolidWorksSimulationgivestheflexibilitytouseautomatictime

steppingalgorithmandmanualsettingoftimesteps.

Now, we are going to start with Non-linear Static Analysis which means

thereisnodampingorresistancetotheforce.Notethatthelastexample

in previous chapter, an assembly of wall bracket, was a problem of

Nonlinearstaticanalysisbecausetherewaslargedisplacementinthebody.

Now, we will learn the procedures of SolidWorks Simulation to perform

Nonlinearstaticanalysis.

StartingNonlinearStaticAnalysis•Openthepartonwhichyouwanttoperformtheanalysis.



performed,willbedisplayedintheleft.

• Click on the Nonlinear button and then on the Static button from the

Optionsrollout;refertoFigure-6.


•ClickontheOKbuttonfromthePropertyManager.ThetoolsrelatedtoNon-linearStaticanalysiswillbedisplayed.Notethatmostofthetoolsaresameasdiscussedinpreviouschapters.

ApplyingMaterial•ClickontheApplyMaterialbuttonfromtheRibbon.TheMaterial dialogboxwillbedisplayedasdiscussedinearlierchapters.

•SelecttheAISI1035Steel(SS)optionfromtheleftlistandclickontheApplybutton.

•ClickontheClosebuttonfromthedialogboxtoexit.Thematerialwillbeapplied;refertoFigure-7.

Figure-7.Modelafterapplyingmaterial

ApplyingFixtures•ClickonthedownarrowbelowFixturesAdvisorintheRibbon.Thetoolsrelatedtofixtureswillbedisplayed.



•Selecttheleftflatfacesofthemodel;refertoFigure-9.

Figure-9.Facesfixedforanalysis

• Click on theOK button from the PropertyManager. The holes will befixedasiftheyareboltedatsameposition.

ApplyingTimeVaryingForce• Click on the down arrow below External Loads Advisor button in the

Ribbon.Listofthetoolsrelatedtoloadswillbedisplayed.

•ClickontheForcebuttonfromthelist.TheForce/TorquePropertyManagerwillbedisplayed;refertoFigure-10.

•NotethatVariationwithTimerolloutisaddedinthePropertyManagerandtworadiobuttonsaredisplayednamed,LinearandCurve.OnselectingtheLinearradiobutton,theforcewillgraduallyincreasetillitreachestothe specified force value within the 1 second of time span; refer to

Figure-11.


Figure-11.Timecurveforlinearvariation

•ClickontheCurveradiobuttonfromtheVariationwithTimerollout.TheEditbuttonwillbecomeactive.

•ClickontheEditbutton.TheTimecurvedialogboxwillbedisplayedasshowninFigure-12.

Figure-12.Timecurvedialogbox

•Clickinthe2ndrowoffirstcolumnandspecifythetimeas20inthe

field.Inthesameway,clickinthe2ndrowofthe2ndcolumnandspecify

theforcevalueas10;refertoFigure-13.

Figure-13.Timecurvedialogboxforcustomization

•ClickontheOKbuttonfromthedialogboxandthenselecttheedgeas

showninFigure-14toapplytheforce.

Figure-14.Edgeselectedforapplyingforce

•ClickontheSelecteddirectionradiobuttonfromtheForce/Torquerollout.Youareaskedtoselectadirectionreference.

•Selectthetopfaceofthemodel;refertoFigure-15.

Figure-15.Faceselectedforforcedirection

•Now,clickonthethirdbuttoni.e.NormaltoPlaneandspecifytheforcevalueas10N;refertoFigure-16.

• Note that if you click on theView button from theVariationwithTimerollout;thegraphwillbedisplayedwiththetotalforceof10x10=100N;refertoFigure-17.

Figure-16.ButtontobeselectedfromForcerollout

Figure-17.Timecurvedialogboxafterentering10inforceeditbox

• Close the dialog box and click on the OK button from the

PropertyManager.Theforcewillbeapplied.

Runningtheanalysis•ClickontheRunbuttonfromtheRibbon.Thesystemwillstartanalyzingtheproblem.Oncethesystemisdone,theresultswillbedisplayedinthe

Modelingarea;refertoFigure-18.NotethatinSolidWorks2015,youcan

alsoseetheintermediateresultsbyselectingthePausebuttonfromtheSolverdialogbox.MakesurethatyouhaveselectedtheShowintermediateresultsuptocurrentstepcheckboxtodisplaytheresults;refertoFigure-19.Ifyoufindthatresultsarenotasperexpectationthenclickonthe

Cancelbuttonandperformthechanges.

Figure-18.Result

Figure-19.Nonlinearanalysissolverdialogbox

Youcaninterprettheresultsasdiscussedinpreviouschapter.

SETTINGPROPERTIESFORNON-LINEAR

STATICANALYSISIt is very important to understand the basic properties of Non-linear

analysisandhowthechangesinpropertiesaffecttheanalysis.Thesteps

belowwilltakeyouthroughvariouspropertysettings.

•AfterstartingNon-linearstaticanalysis,clickontheStudy PropertiestoolfromtheStudyAdvisordrop-downintheRibbon.ThedialogboxwillbedisplayedasshowninFigure-20.

Figure-20.Non-linearstaticanalysispropertiesdialogbox

TheoptionsinSteppingoptions area of the dialog box are used to modifythestarttime,endtime,andincrementalsteps.Forexample,youcancheck

theeffectofloadonacomponentstartingat0secondofloadingtill15

secondafterloading.Also,youwanttochecktheeffectofloadingafter

every3seconds.

•Notethatthestarttimeofanalysisisfixed.Tochangetheendtimefor

analysis,clickintheEndtimeeditboxandchangethevalueasrequired(say15second).

•Tochangethevalueoftimeincrement,selecttheFixedradiobuttonandspecifythedesiredvalueintheeditbox.

•TheoptionsintheGeometricnonlinearityoptionsareaareusedtomodifyoptionsrelatedtogeometricnonlinearity.Therearethreecheckboxesin

this area. Select theUse large displacement formulation check box to usetheformulaoflargedisplacement.Itisimportanttoselectthischeck

box when you that the stiffness matrix will change according to the

loading. Select theUpdate load direction with deflection check box if youwanttocheckthedirectionofdeflectionduringtheloading.Selectthe

Largestrainoptioncheckboxifyouarecheckingthedeflectionofplasticmaterials.

•Selectthedesiredsolverasdiscussedearlier.

•Ifyouwanttousepre-stressesofSolidWorksPlasticsthenclickonthe

In-moldstressestabinthedialogboxandselecttheImportin-moldstressesfromSOLIDWORKSPlasticscheckboxtoactivatetheoption.ClickontheBrowsebuttonandselecttheexportedfileofSolidWorksPlastics.

• Select the Include material from SOLIDWORKS Plastics check box to

include the material of component in current analysis from SolidWorks

Plastics.

•ClickontheOKbuttonfromthedialogboxtoapplysettings.

PERFORMINGNONLINEARSTATICANALYSISONANASSEMBLY

Forperformingnon-linearstaticanalysisonanassembly,weneedtoapply

thecontactsbetweenvariouscomponentsintheassembly.Theprocedureto

performnon-linearanalysisonanassemblyisgivennext.

StartingNon-LinearStaticAnalysis•Openthepartonwhichyouwanttoperformtheanalysis.





Optionsrollout.

•ClickontheOKbuttonfromthePropertyManager.ThetoolsrelatedtoNon-linearStaticanalysiswillbedisplayed.

ApplyingtheMaterial•ClickontheApplyMaterialbuttonfromtheRibbon.TheMaterial dialogboxwillbedisplayed.

• Select the Alloy Steel material from the left and click on the Applybutton. Note that the elastic properties of material will play an

importantroleintheanalysis.

• Click on the Close button from the dialog box. The material will be

applied.


• Click on the Fixed Geometry button from the tool list. The FixturePropertyManagerwillbedisplayed.

•SelectthefacesasshowninFigure-21.

Figure-21.Facesselectedforfixing

•ClickontheOKbuttonfromthePropertyManagertofixthefaces.

ApplyingForces• Click on the down arrow below External Loads Advisor button in the


•ClickontheForcebuttonfromthelist.TheForce/TorquePropertyManager

willbedisplayed.

•NotethatVariationwithTimerolloutisaddedinthePropertyManagerandtworadiobuttonsaredisplayednamed,LinearandCurve.MakesurethattheLinearradiobuttonisselectedintherollout.

•Enterthevalueofforceas10000NintheForceValueeditbox.•SelectthefaceasshowninFigure-22.


Figure-22.faceselectedforforce

ApplyingConnections•ExpandtheComponentContactsnodeandright-clickontheGlobalContact(-Bonded-)option;refertoFigure-23.

Figure-23.Optiontobeselected

•SelecttheDeleteoptionfromtheshortcutmenu.TheSimulationdialogboxwillbedisplayed.

•ClickontheYesbuttontodeletethecontact.

•Clickonthe down arrow belowtheConnectionsAdvisor button and selecttheComponentContactbutton;refertoFigure-24.

Figure-24.ComponentContactbutton

• The Component Contact PropertyManager will be displayed as shown in

Figure-25.

Figure-25.ComponentContactPropertyManager

•SelectthetwocomponentsoftheassemblyasshowninFigure-26.

Figure-26.Componentstobeselected

•ClickontheOKbuttonfromthePropertyManager.Thecontactwillbeaddedbetweenthetwocomponents.

•Again,clickonthedownarrowbelowtheConnectionsAdvisorbuttonandclickontheContactSetbutton.TheContactSetsPropertyManagerwillbedisplayedasshowninFigure-27.


•Selecttheroundfaceofthefirstpartinassembly.

•ClickinthepinkboxintheTyperolloutandselecttheflatfacesoftheblock;refertoFigure-28.

Figure-28.Facesselectedforcontactsets

•SelectthecheckboxnexttoAdvancedrollout.Therolloutwillexpand.

•SelecttheSurfacetosurfaceradiobutton.

•ClickontheOKbuttonfromthePropertyManager.Thecontactswillbeapplied.

Runningtheanalysis•ClickontheRunbuttonfromtheRibbon.Theanalysiswillstart.•Notethatsincethefacesthatweselectedlaterarenotincontactto

eachother,sothedialogboxwiththerelatedmessage;refertoFigure-

29.

Figure-29.NonlinearAnalysisdialogbox

• Click on theNo button from the dialog box since we want to run theanalysis with these conditions only. System will start solving the

analysis.

• On completion of the analysis, the result will be displayed; refer to

Figure-30.

Figure-30.Analysisresult

•Notethatthestressisalsoinducedintheblockbelowthebeambecause

oftheforceinducedonthebeam.

•Youcanchangethecontactbetweenthesurfaceofthebeamandblockto

AllowPenetrationusingtheContactSetsbuttonandcheckfortheresultsforyourinterest.

• To animate any of the result, right-click on the result name from the

AnalysisManager and select theAnimate button from the shortcut menu;refertoFigure-31.

Figure-31.Animatebutton

•Asimulationwillbeplayedforthecurrentselectedresult.

PERFORMINGNONLINEARSTATICANALYSISONARINGUNDERAPPLICATIONOFTORQUE

Themodelusedinthisexampleisaringofcastironundertheloadofa

torque.Thestepstoperformtheanalysisaregivennext.

StartingNon-LinearStaticAnalysis•Openthepartonwhichyouwanttoperformtheanalysis.





Optionsrollout.

•ClickontheOKbuttonfromthePropertyManager.Thetoolsrelatedto

Non-linearStaticanalysiswillbedisplayed.

ApplyingtheMaterial•ClickontheApplyMaterialbuttonfromtheRibbon.TheMaterial dialogboxwillbedisplayed.

• Select the Alloy Steel material from the left and click on the Applybutton.

• Click on the Close button from the dialog box. The material will be

applied.



•SelectthefacesasshowninFigure-32.ClickontheOKbuttontoapply

fixture.

Figure-32.Faceselectedforfixture

•Sincethisisaroundpartandcandeviatefromitsaxis,soweneedto

restrictmovementofitsaxis.

•ClickagainonthedownarrowbelowtheFixturesAdvisorbuttonandselecttheFixed Hinge button from the tool list. The Fixture PropertyManagerwillbedisplayed;refertoFigure-33.


•Selecttheinnerroundfaceofthemodeltomakeisfixedhinge;referto

Figure-34.

Figure-34.Roundfaceselectedforfixedhinge

• Click on theOK button from thePropertyManager to create the fixedhinge.

ApplyingForces• Click on the down arrow below External Loads Advisor button in the


• Click on the Torque button from the list. The Force/TorquePropertyManagerwillbedisplayed.

•NotethatVariationwithTimerolloutisaddedinthePropertyManagerandtworadiobuttonsaredisplayednamed,LinearandCurve.MakesurethattheLinearradiobuttonisselectedintherollout.

•Enterthevalueofforceas1000NintheForceValueeditbox.•SelectthefaceasshowninFigure-35.

Figure-35.Faceselectedforapplyingtorque

•ClickinthepinkboxinPropertyManagerandselecttheinnerroundfacethatwasselectedforfixedhinge.Previewofthetorquewillbeselected.

• If change of torque direction is required then click on the Reversedirectioncheckbox.ClickontheOKbuttonfromthePropertyManagerto

applythetorque.

Runningtheanalysis•ClickontheRunbuttonfromtheRibbon.Theanalysiswillstart.• After the processing is complete, the results will be displayed in the

modelingarea;refertoFigure-36.

Figure-36.Resultonapplyingtorque

2DSIMPLIFICATION2D Simplification is a method of converting simple 3D models to 2D

geometriessothatanalysiscanbeperformedfaster.Use2DSimplification

optionisavailableforStatic,Non-LinearStatic,Non-LinearDynamic,and

Thermal analysis. In this chapter, we will discuss the Non-Linear Static

analysis using 2D simplification. The same method is also applicable for

otheranalyses. The procedure to perform non-linear static analysis using

2Dsimplificationisgivennext.

StartingNon-LinearStaticAnalysiswith2DSimplification•Openthepartonwhichyouwanttoperformtheanalysis.





Optionsrollout.

•SelecttheUse2DSimplificationcheckboxfromtheOptionsrollout.

• Click on the OK button from the PropertyManager. The Nonlinear (2DSimplification)PropertyManagerwillbedisplayed;refertoFigure-37.

Figure-37.Nonlinear(2DSimplification)PropertyManager

•TherearefourbuttonsintheStudyTyperolloutofthePropertyManager;PlaneStress,PlaneStrain,ExtrudeandAxi-symmetric.

•SelectthePlaneStressbuttonifyouwanttoanalyzethingeometrieswithonedimensionlargerthantheothers.Notethatthestressactingnormalto

the section plane is assumed as zero or negligible. This button is not

availableforthermalstudy.

•SelectthePlaneStrainbuttonifyouwanttoanalyzewiththickgeometryassumingstrainperpendiculartosectionplaneiszeroornegligible.This

buttonisnotavailableforthermalstudy.

•SelecttheExtrudebuttonifthermalloadisconstantalongtheextrusiondirection.Thisbuttonisavailableforthermalstudyonly.

•SelecttheAxi-symmetricbuttonwhenthegeometry,materialproperties,structural and thermal loads, fixtures, and contact conditions are

symmetric(3600)aboutanaxis.

•IfyouhaveselectedthePlaneStress orPlane Strain button then selectthesectionplaneandenterthedesiredsectiondepth;refertoFigure-38.

If you have selected the Axi-symmetric button then select the section

planeandaxisaboutwhichthepartissymmetric;refertoFigure-39.

Figure-38.2DsimplificationusingPlanestressbutton

Figure-39.2DsimplificationusingAxi-symmetricbutton

•ClickontheOKbuttonfromthePropertyManagerafterselectingdesiredoptions.The2Dsimplifiedgeometryofthemodelwillbedisplayed;refer

toFigure-40.

Figure-40.Axi-symmetric2Dsimplifiedgeometrycreated

ApplyBoundaryConditions•Applymaterial,fixtureandotherboundaryconditionsasrequired;refer

toFigure-41.

Figure-41.Boundaryconditionsfor2Dmodel

InterpretingResults•RuntheanalysisbyusingRunThisStudybutton.Inafewmoments,youwillgettheresultofanalysis;refertoFigure-42.

Figure-42.Resultofanalysison2Dsimplifiedmodel

•Notethattheresultisdisplayedin2Dformbutifyouwanttocheckthe

resultsin3Dthenright-clickonStressresultandselecttheShowas3DPlotoption;refertoFigure-43.

Figure-43.Showas3DPlotoption

Figure-44.Stressplotin3D

PRACTICE1

Check out what happens to the fork under the conditions specified in

Figure-45.Note that the material offorkisAlloySteel and it is in thehandsofanastykid.(Youknowkids!!theydon’texertlinearforces.)

Figure-45.Practice1NonLinearStaticAnalysis

PRACTICE2

Find out the deflection that will occur in the rope if 70 kg load is

applied on the pin in the pulley; refer to Figure-46. Also, analyze the

pulley if 200 kg load is applied on the pin and the rope acts as fixed

steelbar.

Figure-46.Practice2NonLinearAnalysis

SELF-ASSESSMENT

Q1. Which of the following is generally not considered as cause of non-

linearityinNon-linearstaticanalysis?

a.Largedisplacementinbody

b.Non-linearityofmaterial

c.Changingcontactconditions

d.Changeinforce

Q2.Selectthe………….checkboxintheNonlinear-staticPropertiesdialogboxtousetheformulaoflargedisplacement.

Q3. If you want to use pre-stresses of SolidWorks Plastics then click on

the…………..tabintheNonlinear-staticPropertiesdialogbox.

Q4.Theequationforlinearstaticanalysisisgivenas…………..

Q5.TheequationforNewton-RaphsonMethodofnon-linearanalysisisgiven

as………………..

Q6.IncontextofNon-linearanalysis,multiplesub-stepsareusedtoapply

theloadgraduallyandeachsub-steprepresentsoneloadincrement.(T/F)

Q7.Youcanseetheintermediateresultsinnon-linearanalysisifyouhave

selectedtheShowintermediateresultsuptocurrentstepcheckboxintheNonlinearanalysissolverdialogbox.

Non-LinearDynamicAnalysis

Chapter6

TopicsCovered


•Introduction

•StartingNon-LinearDynamicAnalysis.

•UnderstandingIterationtechniquesandIntegrationmethods


•DefiningFixtures

•Applyingloads


•SimulatingAnalysis


•ResponseGraphs

NONLINEARDYNAMICANALYSISInlinearstaticanalysis,theloadsareappliedgraduallyandslowlyuntil

theyreachtheirfullmagnitude.Afterreachingtheirfullmagnitude,the

loadsremainconstant(time-invariant).Theaccelerationsandvelocitiesof

the excited system are negligible, therefore, no inertial and damping

forcesareconsideredintheformulation:

[K]{u}={f}

where:

[K]:stiffnessmatrix

{u}:displacementvector

{f}:loadvector

Thesolutionproducesdisplacements,stresses,thatareconstant.

Inlineardynamicanalysis,theappliedloadsaretime-dependent.Theloads

can be deterministic (periodic, non-periodic), or non-deterministic which

means that they cannot be precisely predicted but they can be described

statistically. The accelerations and velocities of the excited system are

significant,therefore,inertialanddampingforcesshouldbeconsideredin

theformulation:

where:

[K]:stiffnessmatrix

[C]:dampingmatrix

[M]:massmatrix

{u(t)}:timevaryingdisplacementvector

:timevaryingaccelerationvector

:timevaryingvelocityvector

{f(t)}:timevaryingloadvector

Theresponseofthesystemisgivenintermsoftimehistories(amplitudes

versus time), or in terms of frequency spectra (peak values versus

frequency).

Forlineardynamicanalysis,themass,stiffness,anddampingmatricesdo

not vary with time. Can you guess for what type of analysis they change

withthetime?TheanswerisNon-linearDynamicAnalysis.

PreparingPartandStartingNonlinearDynamicAnalysis• Open the Windshield ball.SLDASM file from resource kit on which the

analysisisnotbeperformed.Inthisfile,youwillseeamodelofball

striking to the model of windshield. Note that a major section of

windshieldisnotgoingtoplayroleintheanalysis.Soitisbetterto

removetheextrasectionofwindshieldbyusingthemodelingtools.

•ClickontheExtrudeCuttoolfromtheAssemblyFeaturesdrop-downoftheAssemblyCommandManagerintheRibbon;refertoFigure-1.Youwillbeaskedtoselectthesketchingplane.

Figure-1.ExtrudeCuttool

• Click on the FeatureManager Design Tree button in the left pane and

selecttheTopPlane;refertoFigure-2.ThetoolsforsketchingwillbeactivatedintheSketchCommandManager.PressCTRL+8(notthenumpad)fromthekeyboardtomakethesketchingplaneparalleltoscreen.

Figure-2.SelectingTopplane

• Create a rectangle cutting half of the windshield; refer to Figure-3.

Click on theExit Sketch button at the top-left corner from the SketchCommandManager.

Figure-3.Rectangletobecreated

• Select theThrough All option from theDirection 1 rollout in theCut-Extrude PropertyManager and click on the OK button from the

PropertyManager.ThemodelwillbedisplayedasshowninFigure-4.




•ClickontheNonlinearbuttonandthenontheDynamic button from theOptionsrollout;refertoFigure-5.

Figure-4.Modelafterextrudecut


•ClickontheOKbuttonfromthePropertyManager.ThetoolsrelatedtoNon-linearDynamicanalysiswillbedisplayed.Notethatmostofthetoolsaresameasdiscussedinpreviouschapters.

WeknowthattheNonlinearDynamicanalysisisstudyofdeformationaswell

askinematics.Here,wehaveanexampleofcarwindshield(madeofAcrylic

plastic)andasteelball;refertoFigure-6.Let’sseewhathappens.(Is

itNationalGeographic’sDestroyedinsecondsornot!!)

Figure-6.Exampleofwindshieldandballstudy

ApplyingMaterial• Right-click onWindshield under theParts category inAnalysisManagerand click on theApply/EditMaterial option from the shortcut menu. TheMaterialdialogboxwillbedisplayed.

•Selectthedesiredmaterial,whichisAcrylic(Medium-highimpact)inthePlastic category from the left list in the dialog box and click on theApplybutton.

•ClickontheClosebuttonfromthedialogboxtoexit.Similarly,applythe Alloy Steel material to ball in the Steel category. The colors of

modelswillbechanged;refertoFigure-7.





•Selecttopandbottomflatfacesofthewindshield;refertoFigure-9.

Figure-9.Facestobefixed

• Click on theOK button from the PropertyManager. The holes will befixedasiftheyareboltedatsomeposition.

ApplyingNoPenetrationContact•Toapplynopenetrationcontactbetweenthecomponents,weneedtoremove

theglobalcontactwhichisbondedbydefault.Todoso,right-clickon

the Component Contacts option from the Connections category in the

AnalysisManager.Ashortcutmenuwillbedisplayed;refertoFigure-10.

Figure-10.Deleteoptionforcontacts

•SelecttheDeleteoptiontodeletethedefaultcontact.Awarningmessagewillbedisplayed.ClickontheYesbuttonfromthedialogbox.

• Click on theContact Set tool from theConnectionsAdvisor drop-down intheRibbon.TheContactSetsPropertyManagerwillbedisplayed.

• Click on the front faces of the Windshield part from the viewport and

thenclickintheselectionboxforsecondset.

•Clickontheroundaceoftheball;refertoFigure-11.

Figure-11.Facesselectedforcontactset

•ClickontheOKbuttonfromthePropertyManagertoapplycontact.

SettingInitialConditions•ClickontheInitialConditiontoolfromtheRibbon.TheInitialConditionsPropertyManagerwillbedisplayed;refertoFigure-12.

Figure-12.InitialConditionsPropertyManager

•SelecttheVelocityradiobuttonfromthePropertyManagertoapplyinitialvelocitytoball.

•ClickontheballpartfromFeatureManagerDesignTreeintheviewport.• Click in the next selection box used for direction and select the Top

planeofassemblyfordirection;refertoFigure-13.

Figure-13.Topplaneselectedfordirectionreference

• Select the Normal to Plane button from the Velocity rollout in the

PropertyManagerandspecifythevalueas5inthecorrespondingeditboxwithReversedirectioncheckboxselected;refertoFigure-14.Notethattocheckthedirectionofforce,youneedtohoverthecursorontheball.

Figure-14.Velocityspecifiedforball

• Click on the OK button from the PropertyManager to apply initial

condition.

GlobalDampingGlobal Damping option is available in all the dynamic analyses in

SolidWorksSimulationsinceweneedtospecifythedampingcoefficientfor

thestudy.Now,assumethatthesystemonwhichwearegoingtoperformthe

studyissubmergedinoil.ToletSolidWorksSimulationunderstandthatour

system is submerged in a kind of oil, we need to specify global damping

matrix.Thestepstodosoaregivennext.

•ClickontheGlobalDampingbuttonfromtheRibbon.TheRayleighdampingPropertyManagerwillbedisplayed;refertoFigure-15.

Figure-15.RayleighdampingPropertyManager

•SpecifythedampingparametersasrequiredandclickontheOKbutton.

Note that for this particular problem, we do not have any damping

conditionsspecifiedsowewillnotapplydamping.

RayleighDampingRayleighdamping has certain mathematical conveniences and is widely used

tomodelinternalstructuraldamping.ThedampingmatrixCisgivenbyC=

αM+βKwhereM,Karethemassandstiffnessmatricesrespectivelyandα,

βareconstantsofproportionality.Oneofthelessattractivefeaturesof

Rayleigh damping is that the achieved damping ratio varies as response

frequencyvaries.Thestiffnessproportionaltermcontributesdampingthat

is linearly proportional to response frequency and the mass proportional

term contributes damping that is inversely proportional to response

frequency.Mathematically,thesefrequencydependenciescanbeseeninthe

formula for damping ratio ξ = π(α/f + βf) where f is the response

frequency.

The plot in Figure-16 illustrates how the separate mass and stiffness

dampingtermscontributetotheoveralldampingratio(Valueofαis0.025

andβis0.023):

Figure-16.DampingratioforRayleighDamping

ApplyingForce

•ClickontheForcetoolfromtheExternalLoadsAdvisordrop-downintheRibbon.TheForce/TorquePropertyManagerwillbedisplayed.

•SelecttheroundfaceofballandtheselecttheSelecteddirection radiobutton from the PropertyManager. The selection box for direction

referencewillbedisplayed.

•SelecttheTopPlaneofassemblyagain.

•ClickontheNormal toPlane button from theForce PropertyManager andspecify the value as 500 in the corresponding edit box with Reversedirectioncheckboxselected;refertoFigure-17.

Figure-17.Forceappliedonball



Modelingarea.

Youcaninterprettheresultsasdiscussedinearlierchapters.

SETTINGPARAMETERSINNONLINEARDYNAMICANALYSIS

Asdiscussedinpreviouschapter,themethodtosolvenonlinearequationis

Newton-Raphson method which is applicable for nonlinear dynamic analyses

also. Before we start analyzing the model, we are required to set a few

optionsinPropertiesdialogbox.Theproceduretodosoisgivennext.

•Afterstartingthenonlineardynamicanalysis,clickonStudy Propertiesbutton from the Study Advisor drop-down in the Ribbon. The NonlinearDynamicdialogboxwillbedisplayed;refertoFigure-18.

Most of the options in the dialog box are same as discussed in previous

chapters. We can set the time steps as discussed earlier. Here, we will

discuss the advanced options which have not been discussed in previous

chapters.

Figure-18.Nonlinear-Dynamicdialogbox

•ClickontheAdvancedOptionsbuttonfromthedialogbox.TheAdvancedtabwillbeaddedinthedialogbox;refertoFigure-19.

Figure-19.PartialviewofAdvancedtab

• Click in the Iterative technique drop-down and select the desired

technique. There are two options in the drop-down;Newton-Raphson andModifiedNewton-Raphson.TheNewton-RaphsonmethodsolvesequationuptofirstderivativeoffunctionwhereasmodifiedNewton-Raphsonmethodsolves

equation up to second derivative of function. More details of these

optionsaregiveninnexttopic.

•Clickinthedrop-downfor Integration and select the desired option touse as integration method. There are three options in this drop-down;

Newmark, Wilson-Theta, and Central Difference. The details of these

optionsisgivenafternexttopicinthischapter.

•Settheconvergencetoleranceandstepparametersandthenclickonthe

OKbuttonfromthedialogboxtoapplysettings.

Newton-RaphsonandModifiedN-RMethod

ForNewton-RaphsonMethod:

ForModifiedNewton-RaphsonMethod:

From the equations, we can understand that the Modified Newton-Raphson

methodisfasterformultiplerootequationbecauseittellsslopeaswell

ascurvatureofthefunction.Butforsimplerequationsinwhichweneedto

find out one or two roots it takes more processing than the original

Newton-Raphsonmethod.So,wesuggesttheuseofNewton-Raphsonmethodwhen

youhavesimplerproblemsandforcomplexproblems,youshoulduseModified

Newton-Raphsonmethodasiterativetechnique.

IntegrationMethodAlthoughthereareafewmoreintegrationmethodsbutwewillconcentrate

onthethreemethodsnamedabovesincethesemethodsareusedbySolidWorks

Simulation.

NewmarkMethodNewmark is a type of implicit method for integration which means

differential equations are combined with equations of motions and the

displacementsarecalculatedbydirectlysolvingtheequation.TheNewmark

method also assumes that the acceleration varies linearly between two

instants of time. The equation for velocity and displacement in Newmark

methodcanbegivenbyFigure-20.

Figure-20.EquationforNewmarkBetamethod

Theparametersalphaandbetaareuser-definedandcanbechangedtosuit

therequirementsofparticularproblems.Forexample,puttingα=1/2andβ

=0makestheaccelerationconstantandequaltoẌt.Weknowtheequationof

forceas,

Here[M]ismassmatrixand{Ft+Δt

}isforcematrix

TheEquationsforMassandForcecanbegivenby,

SomeoftheimportantpointsforusingNewmarkbetamethodare:

•InNewmarkmethod,theamplitudeinlinearsystemsisconservedandthe

responseisunconditionallystableif

and

• If alpha = 1/2 and beta = 1/4 then large truncation errors occur in

frequencyofresponse.

•Ifbeta=1/2thenspuriousdampingisintroducedproportionalto(alpha-

1/2).

• If beta is negative then self-excited vibrations arouse and if beta is

greaterthan1/2,apositivedampingisintroduced.

Instraightwords,theselectionofalphaandbetacanmakebigdifference

inresultsofanalysissotheirvalueshouldbedecidedverycarefully.

AlgorithmbasedonNewmarkmethoda.InitialComputations:

1.Formstiffness[K],mass[M],anddamping[C]matrices.

2.Initialize{X0},{Ẋ

0},and{Ẍ

0}.

3. Select the time step Δt, parameters α and β and calculate integration

constants,β≥0.5andα≥0.25(0.5+β)2.

4.Formeffectivestiffnessmatrix:

5.Triangularize

b.ForEachtimestep,calculate:

Wilson-ThetaMethodWilson-Thetamethodisalsoatypeofimplicitmethodforintegration.It

assumes that the acceleration of system varies linearly between two

instants of time ti=iΔt to t

i+θΔt, where θ≥1.0. If τ is time increment

betweentandt+θΔtthenaccelarationisgivenas,

Onsuccessiveintegration,displacementisgivenby,

Puttingvaluesinforceequationweget,

SomeoftheimportantpointsforusingWilsonthetamethodare:

•Whenθ=0thenmethodreducestolinearaccelerationscheme.

•Themethodisunconditionallystableforθ≥1.37.

• A value of θ=1.4 is used for nonlinear dynamic systems which is our

currentstudycase.

• In this method, there is no need to specify initial conditions because

thedisplacement,velocity,andaccelerationarefunctionsoftime.

CentralDifferenceMethodCentral Difference method is a type of explicit method for integration

which means the response quantities are expressed in terms of previously

determined values of displacement, velocity, and acceleration. It is

assumedthatthetimeperiodisdividedintonequalpartsofinterval.The

accuracyofsolutiondependsonsizeoftimestep.Thecriticaltimestep

is given by Δtcri = τ

n/Π, where τ

n is natural period of system. If Δt is

selected larger than Δtcri then method becomes unstable making dynamic

analysis meaningless due to big error. The equation of force for central

differencemethodisgivenby,

Onsolvingfordisplacement,weget

Fromtheequation,youcaneasilyinterpretthatthedisplacementofmass

Xi+1canbecalculatedonlyifyouhavevalueofX

i,X

i-1andpresentforceF

i.

ButinitialconditionsprovideonlyX0andẊ

0 so X

-1 is calculated to find

outX1.FirsttheaccelerationẌ

0iscalculatedandthenthevalueofX

-1is

calculatedbyusingitasgivennext,

NotethatthetimestepshouldbelessthanΔtcriforusingofthismethod

otherwisetheresultswillnotbemeaningful.

PRACTICAL1

In this practical, we will find out response curve of the model under

conditionsgiveninFigure-21.

Figure-21.Practical1nonlineardynamic

StartingNonlinearDynamicAnalysis•Openthepartonwhichyouwanttoperformtheanalysis.




•ClickontheNonlinearbuttonandthenontheDynamic button from theOptionsrollout;refertoFigure-22.


•ClickontheOKbuttonfromthePropertyManager.ThetoolsrelatedtoNon-linearDynamicanalysiswillbedisplayed.Notethatmostofthetoolsaresameasdiscussedinpreviouschapters.

• Select the desired method and integration technique for analysis. For

this practical, we have used Newton-Raphson method with Newmark

integrationtechnique.


•Selectthedesiredmaterial,sayAlloySteeloptionfromtheleftlistandclickontheApplybutton.

•ClickontheClosebuttonfromthedialogboxtoexit.Thecolorofmodelwillbechanged;refertoFigure-23.


ApplyingTimeVaryingTorque• Click on the down arrow below External Loads Advisor button in the


• Click on the Torque button from the list. The Force/TorquePropertyManagerwillbedisplayed.

•Selecttheroundfaceofthemodelandspecifythetorquevalueasshown

inFigure-24.

Figure-24.Torquevaluespecified

•ExpandtheVariationwithTimerolloutinthePropertyManagerandclickontheCurveradiobuttontodefinetheloadingcurve.

•ClickontheEditbuttonfromtheVariationwithTimerolloutanddefinethetimecurveasshowninFigure-25.Notethattoaddanewrowinthe

table,youneedtodouble-clickonthelastfieldunderPointscolumninthetable.

Figure-25.TimeCurvefortorque

•ClickontheOKbuttonfromthedialogboxandthenOKbuttonfromthe

PropertyManager.



•SelecttheholescutfromthemodelasshowninFigure-26.

Figure-26.Holesfixed

•ClickontheOKbuttonfromthePropertyManagertoapplythefixtures.

ApplyingDamping•ClickontheGlobalDampingbuttonfromtheRibbon.TheRayleighdampingPropertyManagerwillbedisplayed.

•Specifythevalueofalphaas2.5inthecorrespondingeditboxandthenclickontheOKbuttonfromthePropertyManager.

Specifyinginitialvelocity• Click on the Initial Conditions button from the Ribbon. The InitialConditionsPropertyManagerwillbedisplayed;refertoFigure-27.

Figure-27.InitialConditionsPropertyManager

•ClickontheVelocityradiobuttonandselecttheroundfaceofthemodel.

• Click in the pink selection box of PropertyManager to define the

direction and then select the round face of the model again; refer to

Figure-28.

Figure-28.Faceselectedfordefiningvelocity

•SelecttheCircumferentialbuttonfromtheVelocityrolloutandspecifythevalueas30inthecorrespondingeditbox;refertoFigure-29.

Figure-29.Circumferentialvelocitydefined


DefiningMeshSinceweareperformingtheanalysisforeducationalpurposeonly,herewe

will define the mesh as coarse. This will reduce the solving time of

analysis.

•ClickonthedownarrowbelowRunThisStudybuttonintheRibbon.Listoftoolswillbedisplayed.

•ClickontheCreateMeshtoolfromthelist.TheMeshPropertyManagerwillbedisplayed.

• Move the slider to extreme left in the Mesh Density rollout in

PropertyManager;refertoFigure-30.

Figure-30.Coarsemeshdensity

•ClickontheOKbuttonfromthePropertyManagertoapplymeshing.

Runninganalysis• Click on theRun This Study button from theRibbon. The intermediateresultsofanalysiswillbedisplayed;refertoFigure-31.Notethatthe

intermediate results display is latest enhancement in SolidWorks

Simulation.

Figure-31.Runningnonlinearanalysis

CreatingTimeresponsecurveAsdiscussedearlier,TimeresponsecurveisthemainresultforanyNon-

linearanalysisbecausestresschangesaspertheforcecurve.Itmightbe

possiblethatthestressisverylowattheendofstudybutveryhighin

the middle of study. So, Time response curve gives the real time

informationofstresswithrespecttotime.ThestepstoaddTimeresponse

curveinresults,aregivennext.

•Right-clickontheResultnodeintheAnalysisManager.Ashort-cutmenuwillbedisplayed;refertoFigure-32.

Figure-32.ShortcutmenuforTimeresponsecurve

•ClickontheDefineTimeHistoryPlotoptionfromtheshortcutmenu.TheTimeHistoryGraphPropertyManagerwillbedisplayed;refertoFigure-33.

• Make sure thatTime is selected in theX axis drop-down and Stress isselectedintheYaxisdrop-downasshowninFigure-33.

Figure-33.TimeHistoryGraphPropertyManager

• Click on theOK button from thePropertyManager. TheResponseGraphwill be displayed; refer to Figure-34. Note that this is the response

graph of node 1 which was selected in the Time History GraphPropertyManagerearlier;refertopreviosfigure(Figure-33).

Figure-34.ResponseGraph

•ClosetheResponseGraphdialogboxandright-clickonResponse1resultintheResultnodeinAnalysisManager;refertoFigure-35.

Figure-35.Shortcutmenuforresponseresult

• Select the Edit Definition option from the shortcut menu and select a

differentnodetochecktheresponse.Like,selectthenode95(Figure-36)

fromthelistandclickOKfromthePropertyManagertoseetheresponsegraph(Figure-37).

Figure-36.Node95

Figure-37.ResponseGraphfornode95

• In this way, you can check the response graph of critical areas. Note

that the stress of this node has gone up to 1.566x108 but in Stress1

result,wedon’tfindanyspotwithsuchhighstress;refertoFigure-38.

So,youcannowunderstandwhyResponsegraphisimportantincaseofnon-

linearanalyses.

Figure-38.Comparingstressresults

PRACTICE1

A sheet metal plate of 140mmX40mmX3mm is placed on bending machine

withbendinglineatthecenterofplatealonglength.Theloadappliedby

bendingmachineonplateis100kgf.Findoutifplatewillbendornot.

SELF-ASSESSMENT

Q1.Forlineardynamicanalysis,themass,stiffness,anddampingmatrices

donotvarywithtime.(T/F)

Q2.GlobalDampingoptionisnotavailableinalltypeofdynamicanalyses

inSolidWorksSimulation.(T/F)

Q3.CentralDifferencemethodisatypeofexplicitmethodofintegration.

(T/F)

Q4.InaNon-linearanalysisstresschangesaspertheforcecurve.(T/F)

Q5. Which of the following condition is required for stable solution of

NewmarkIntegrationMethod?

a.α≥0.5andβ≥0.25(α+0.5)2

b.α≤0.5andβ≥0.25(α+0.5)2

c.α≥0.5andβ≤0.25(α+0.5)2

d.α≤0.5andβ≤0.25(α+0.5)2

Q6.Inallcases,theModifiedNewton-Raphsonmethodisfasterbecauseit

tellsslopeaswellascurvatureofthefunction.(T/F)

Q7. Newmark is a type of implicit method for integration which means

differential equations are combined with equations of motions and the

displacementsarecalculatedbydirectlysolvingtheequation.(T/F)

FrequencyAnalysis

Chapter7

TopicsCovered


•Introduction

•StartingFrequencyAnalysis.


•DefiningFixtures

•Applyingloads




INTRODUCTIONEverystructurehasthetendencytovibrateatcertainfrequencies,called

natural or resonant frequencies.Eachnaturalfrequencyisassociatedwithacertain shape, called mode shape, that the model tends to assume when

vibratingatthatfrequency.

When a structure is properly excited by a dynamic load with a frequency

thatcoincideswithoneofitsnaturalfrequencies,thestructureundergoes

large displacements and stresses. This phenomenon is known as resonance.For undamped systems, resonance theoretically causes infinite motion.

Damping,however,putsalimitontheresponseofthestructuresduetoresonantloads.

A real model has an infinite number of natural frequencies. However, a

finite element model has a finite number of natural frequencies that are

equaltothenumberofdegreesoffreedomconsideredinthemodel.Onlythe

firstfewmodesareneededformostpurposes.

Ifyourdesignissubjectedtodynamicenvironments,staticstudiescannot

be used to evaluate the response. Frequency studies can help you design

vibration isolation systems by avoiding resonance in specific frequency

band. They also form the basis for evaluating the response of linear

dynamicsystemswheretheresponseofasystemtoadynamicenvironmentis

assumed to be equal to the summation of the contributions of the modes

consideredintheanalysis.

Notethatresonanceisdesirableinthedesignofsomedevices.Forexample,resonanceisrequiredinguitarsandviolins.

The natural frequencies and corresponding mode shapes depend on the

geometry, material properties, and support conditions. The computation of

natural frequencies and mode shapes is known as modal, frequency, and

normalmodeanalysis.

Whenbuildingthegeometryofamodel,youusuallycreateitbasedonthe

original(undeformed)shapeofthemodel.Someloads,likethestructure’s

own weight, are always present and can cause considerable effects on the

shapeofthestructureanditsmodalproperties.Inmanycases,thiseffect

canbeignoredbecausetheinduceddeflectionsaresmall.

Loadsaffectthemodalcharacteristicsofabody.Ingeneral,compressive

loads decrease resonant frequencies and tensile loads increase them. This

factiseasilydemonstratedbychangingthetensiononaviolinstring.The

higherthetension,thehigherthefrequency(tone).

You do not need to define any loads for a frequency study but if you do

theireffectwillbeconsidered.Byhavingevaluatednaturalfrequenciesof

a structure’s vibrations at the design stage, you can optimize the

structurewiththegoalofmeetingthefrequencyvibro-stabilitycondition.

To increase natural frequencies, you would need to add rigidity to the

structureand(or)reduceitsweight.Forexample,inthecaseofaslender

object,therigiditycanbeincreasedbyreducingthelengthandincreasing

the thickness of the object. To reduce a part’s natural frequency, you

should, on the contrary, increase the weight or reduce the object’s

rigidity.

Note that the software also considers thermal and fluid pressure effects

forfrequencystudies.

Theproceduretoperformthefrequencyanalysisisgivennext.

STARTINGFREQUENCYANALYSIS•Openthepartonwhichyouwanttoperformtheanalysis.




• Click on the Frequency button then click on theOK button from the

PropertyManager. The tools related to frequency analysis will be

displayed.

ApplyingMaterial•ClickontheApplyMaterialbuttonfromtheRibbon.TheMaterial dialogboxwillbedisplayed.

•ExpandtheSolidWorksMaterialsnodeandthentheAluminiumAlloysnodeintheleftofthedialogbox.

•BrowsethroughthematerialsandselecttheAluminamaterial.

• Click on theApply button and then click on theClose button from thedialogboxtoexitthedialogbox.

ApplyingFixtures

•ClickonthedownarrowbelowFixturesAdvisorintheRibbon.Thetoolsrelatedtofixtureswillbedisplayed.


•SelectthefaceofthemodelasshowninFigure-1.


Figure-1.Faceforfixture

ApplyingForcesNotethatitisnotnecessarytoapplyforcesforperformingtheFrequency

analysisbutifyouapplytheforces,theyarecountedfortheireffectsin

deformation.Theydonotmakeanyeffectonresonancefrequencies.

•ClickonthedownarrowbelowExternalLoadsAdvisorfromtheRibbon.Thelistoftoolswillbedisplayed.

• Click on the Force button from the list. The Force/TorquePropertyManagerwillbedisplayed;refertoFigure-2.


•SelectthefaceasshowninFigure-3.andspecifytheforcevalueas100

N.

Figure-3.Forcetobeapplied


SettingParametersfortheanalysis•Right-clickonthenameofanalysisintheAnalysisManager.Ashortcutmenuwillbedisplayed;refertoFigure-4.

Figure-4.Shortcutmenuforproperties

• Click on the Properties button from the shortcut menu. The Frequencydialogboxwillbedisplayed;refertoFigure-5.

•Inthisdialogbox,theNumberoffrequenciesspinnerisusedtospecifythenumberofnaturalfrequenciesthataretobefoundout.

•Ifyouwanttocheckthenaturalfrequencyclosertoaspecificfrequency

then select theCalculate frequencies closest to: (Frequency Shift) check boxandspecifythevalueoffrequencyintheadjacenteditbox.

•AsweareapplyingforcewithintheFrequencyanalysis,thenweneedto

select theDirect sparse Solver from the Solver area in the dialog box.Otherwise,anerrorwillbegenerated.

Figure-5.Frequencydialogbox

•Otheroptionsinthedialogboxhavealreadybeendiscussed.


Runningtheanalysis•ClickontheRunbuttonfromtheRibbontoruntheanalysis.Thesolvingprocessofanalysiswillstart.

• After the process is complete, the results will be displayed; refer to

Figure-6.

Figure-6.ResultofFrequencyanalysis

•TherearesixnodesdisplayedunderResultsintheAnalysisManagerwhichrepresentsixmodeshapesatrespectivenaturalfrequencies.

• From the results, you find that our part should not be working in the

rangeofthenaturalfrequencieslisted.

•Todisplaythelistofresonantfrequencies,right-clickontheResultsnodeintheAnalysisManager.Ashortcutmenuwillbedisplayed.

•ClickontheListResonantFrequenciesbuttonfromtheshortcutmenu;refertoFigure-7.

Figure-7.Shortcutmenuforresults

• TheListModes dialog box will be displayed. TheFrequency (Hz) columnshowstheresonantfrequencies;refertoFigure-8.

Figure-8.ListModesdialogbox

SELF-ASSESSMENT

Q1. Every structure has the tendency to vibrate at certain frequencies,

called…………..or…………frequencies.

Q2.Eachnaturalfrequencyisassociatedwithacertainshape,called……………

Q3.Thestructureundergoeslargedisplacementsandstressesundertheload

with frequencies coinciding with its natural frequencies. This phenomenon

isknownas…………….

Q4. Frequency studies can help you design vibration isolation systems by

avoidingresonanceinspecificfrequencyband.(T/F)

Q5.Toincreaseapart’snaturalfrequency,youshouldincreasetheweight

orreducetheobject’srigidity.(T/F)

Q6. For undamped systems, resonance theoretically causes infinite motion.

(T/F)

Q7.Arealmodelhasaninfinitenumberofnaturalfrequencies.(T/F)

Q8. ………… analysis can help you design vibration isolation systems by

avoidingresonanceinspecificfrequencyband.


Chapter8

TopicsCovered


•Introduction

•TypesofLinearDynamicAnalysis

•StartingLinearDynamicAnalysis.


•DefiningFixtures

•Applyingloads




LINEARDYNAMICANALYSISStaticstudiesassumethatloadsareconstantorappliedveryslowlyuntil

theyreachtheirfullvalues.Becauseofthisassumption,thevelocityand

acceleration of each particle of the model is assumed to be zero. As a

result,staticstudiesneglectinertialanddampingforces.

Formanypracticalcases,loadsarenotappliedslowlyortheychangewith

time or frequency. For such cases, use a dynamic study. Generally if the

frequency of a load is larger than 1/3 of the lowest (fundamental)

frequency,adynamicstudyshouldbeused.

Linear dynamic studies are based on frequency studies. The software

calculates the response of the model by accumulating the contribution of

eachmodetotheloadingenvironment.Inmostcases,onlythelowermodes

contribute significantly to the response. The contribution of a mode

depends on the load’s frequency content, magnitude, direction, duration,

andlocation.

Objectivesofadynamicanalysis• Design structural and mechanical systems to perform without failure in

dynamicenvironments.

• Modify system’s characteristics (i.e. geometry, damping mechanisms,

materialproperties,etc.)toreducevibrationeffects.

TherearefourtypeofdynamicanalysesthatcanbeperformedinSolidWorks

Simulation:

•ModalTimeHistoryAnalysis

•HarmonicAnalysis

•RandomVibrationAnalysis

•ResponseSpectrumAnalysis

Beforewestartknowingaboutvariousdynamicanalyses,itisimportantto

understandtheconceptofdamping.

DampingIf you apply initial conditions to a dynamic system, the system vibrates

with decreasing amplitudes until it comes to rest. This phenomenon is

calleddamping.Dampingisacomplexphenomenonthatdissipatesenergyby

many mechanisms like internal and external friction, thermal effects of

cyclic elastic straining materials at the microscopic level, and air

resistance.

Itisdifficulttodescribedissipationmechanismsmathematically.Damping

effectsareusuallyrepresentedbyidealizedmathematicalformulations.For

manycases,dampingeffectsareadequatelydescribedbyequivalentviscous

dampers.

A viscous damper (or dashpot) generates a force that is proportional to

velocity. A piston that can move freely inside a cylinder filled with a

viscousfluidlikeoilisanexampleofaviscousdamper.

Thefollowingtypesofdampingareavailable:

ModalDamping

RayleighDamping

CompositeModalDamping

Concentrated Dampers. Defined between two locations (available for modal

timehistoryanalysis).

WehavediscussedaboutRayleighDampinginpreviouschapters.Now,wewill

discussabouttheotherdampingoptions.

ModalDampingModal damping is defined as a ratio of the critical damping C

c for each

mode. Critical damping Cc is the least amount of damping that causes a

systemtoreturntoitsequilibriumpositionwithoutoscillating.

The modal damping ratio can be determined accurately with proper field

tests. The ratio varies from 0.01 for lightly damped systems to 0.15 or

moreforhighlydampedsystems.

Whenexperimentaldataisnotavailable,usedatafromasimilarclassof

systems to determine the damping properties. Smaller ratios are more

conservative since higher ratios reduce vibration amplitudes. In general,

neglecting damping leads to a conservative estimate of the system’s

response.

Inmathematicalterms,dampingratioisgivenby

Here,Cc=2mω

n

Dampingratiosfordifferentsystemsandmaterialsaregivenas:

CompositeModalDampingCompositemodaldampingallowsthedefinitionofthedampingasamaterial

property. Material damping ratio is defined in the Properties tab of theMaterialdialogbox.Theprogramusesthispropertytocalculateequivalentmodaldampingratioforeachmode.

Thecompositemodaldampingisdefinedintermsofequivalentmodaldamping

ratiosas:

βj={φ}

j

T {φ}j

where:

βj=equivalentmodaldampingratioofthejthmode

{φ}j

T=jthnormalizedmodaleigenvector

= modified global mass matrix constructed from the product of the

element’sdampingcoefficientanditsmassmatrix.

Here,thequestionsrise:WheretouseModaldamping?WheretouseRayleighDamping?WhytheCompositeModaldampingisrequired?

The answer to these questions are not straight forward but they are

dependentofmanyfactorslikematerialstructure,massproperties,damping

systemused,andmanyotherpropertiesofthesystem.

•RayleighDampingschemeallowsusetheflexibilityofusingsystemsthat

change damping force depending on mass matrix and stiffness matrix of

model. If you expect changes to happen in mass or stiffness then you

should use Rayleigh Damping scheme otherwise it is good to use Modal

dampingschemebecauseyouhaveadirectvalueofdampingformostofthe

materials.

• If there is requirement of calculating internal damping of part then

ModaldampingschemeisbetterthanRayleighdampingscheme.

• If the part has softer elements then Rayleigh Damping can product

unrealisticresultsbecauseofstiffnessmatrixpart.So,youshoulduse

Modaldamping.

The Composite Modal Damping uses the damping value specified in the

materialproperties.Inthisway,itreducestherequirementofexplicitly

definingdampingvalueforeachobjectinassemblyunderthestudy.

TYPESOFDYNAMICANALYSISOnthebasisoftheuse,theallfouranalysescanbeexplainedasfollows:

ModalTimeHistoryAnalysisUsemodaltimehistoryanalysiswhenthevariationofeachloadwithtime

isknownexplicitlyandyouareinterestedintheresponseasafunctionof

time.

Typicalloadsinclude:

•Shock(orpulse)loads

•Generaltime-varyingloads(periodicornon-periodic)

• Uniform base motion (displacement, velocity, or acceleration applied to

allsupports)

• Support motions (displacement, velocity, or acceleration applied to

selectedsupportsnon-uniformly)

• Initial conditions (a finite displacement, velocity, or acceleration

appliedtoapartorthewholemodelattimet=0).

Thesolutionoftheequationsofmotionformultidegree-of-freedomsystems

incorporatesModalanalysistechniques.

Thesolution’saccuracycanimprovebyusingasmallertimestep.

After running the study, you can view displacements, stresses, strains,

reactionforces,etc.atdifferenttimesteps,oryoucangraphresultsat

specified locations versus time. If no locations are specified in Result

Options,resultsatallnodesaresaved.

Modal, Rayleigh, composite modal, and concentrated dampers are available

formodaltimehistoryanalysis.

HarmonicAnalysisUse harmonic analysis to calculate the peak steady state response due to

harmonicloadsorbaseexcitations.

A harmonic load P is expressed as P = A sin (ωt + φ) where: A is the

amplitude,ωisthefrequency,tistime,andφisthephaseangle.Sample

harmonicloadsofdifferentfrequencieswversustimeareshowninFigure-

1.

Figure-1.Graphforlineardynamicanalysis

Although you can create a modal time history study and define loads as

functionsoftime,youmaynotbeinterestedinthetransientvariationof

the response with time. In such cases, you save time and resources by

solving for the steady-state peak response at the desired operational

frequencyrangeusingharmonicanalysis.

For example, a motor mounted on a test table transfers harmonic loads to

thesupportsystemthroughthebolts.Youcanmodelthesupportingsystem

and define a harmonic study to evaluate the steady-state peak

displacements, stresses, etc. for the motor’s range of operating

frequencies.Youcanapproximatethemotorbyadistributedmass.

After running the study, you can view peak stresses, displacements,

accelerations,andvelocitiesaswellasphaseanglesoftheresponseover

therangeofoperatingfrequencies.

Modal,Rayleigh,andCompositemodaldampingoptionsareavailableforthis

typeofanalysis.

RandomVibrationAnalysisUse a random vibration study to calculate the response due to non-

deterministicloads.Examplesofnon-deterministicloadsinclude:

•Loadsgeneratedonawheelofacartravelingonaroughroad

•Baseaccelerationsgeneratedbyearthquakes

•Pressuregeneratedbyairturbulence

•Pressurefromseawavesorstrongwind

In a random vibration study, loads are described statistically by power

spectral density (psd) functions. The units of psd are the units of the

load squared over frequency as a function of frequency. For example, the

unitsofapsdcurveforpressureare(psi)2/Hz.

The solution of random vibration problems is formulated in the frequency

domain.

Afterrunningthestudy,youcanplotroot-mean-square(RMS)values,orpsd

results of stresses, displacements, velocities, etc. at a specific

frequencyorgraphresultsatspecificlocationsversusfrequencyvalues.

Modal,Rayleigh,andCompositemodaldampingoptionsareavailableforthis

typeofanalysis.

ResponseSpectrumAnalysisInaresponsespectrumanalysis,theresultsofamodalanalysisareused

intermsofaknownspectrumtocalculatedisplacementsandstressesinthe

model.Foreachmode,aresponseisreadfromadesignspectrumbasedon

themodalfrequencyandagivendampingratio.Allmodalresponsesarethen

combinedtoprovideanestimateofthetotalresponseofthestructure.

You can use a response spectrum analysis rather than a time history

analysistoestimatetheresponseofstructurestorandomortime-dependent

loadingenvironmentssuchasearthquakes,windloads,oceanwaveloads,jet

enginethrustorrocketmotorvibrations.

After reading from the above section, we can find that the pattern of forceapplicationchangesinalltheanalyses.Now,wewillstartwiththeRandomVibrationAnalysisandproceedtootherDynamicanalyses.

StartingRandomVibrationAnalysis•Openthepartonwhichyouwanttoperformtheanalysis.


•ClickontheDownarrowbelowtheStudyAdvisorbuttonandselecttheNew

Study tool from the drop-down. List of analysis studies that can be


• Click on the Linear Dynamic button and then on the Random VibrationAnalysisbuttonfromtheOptionsrollout;refertoFigure-2.


•ClickontheOKbuttonfromthePropertyManager.ThetoolsrelatedtoLinear Dynamic Random Vibration analysis will be displayed. Note thatmostofthetoolsaresameasdiscussedinpreviouschapters.


•SelecttheAlloySteeloptionfromtheleftlistandclickontheApplybutton.

•ClickontheClosebuttonfromthedialogboxtoexit.Thecolorofmodelwillbechanged;refertoFigure-3.




•Selecttheroundfacesofthemodel;refertoFigure-4.

Figure-4.Facestobefixed

•ClickontheOKbuttonfromthePropertyManager.Theroundfaceswillbefixedasiftheyareboltedatthatposition.

ApplyingForceVibrations• Click on the down arrow below External Loads Advisor button in the


•ClickontheForcebuttonfromthelist.TheForce/TorquePropertyManagerwillbedisplayed.

•ClickintheForceValueeditboxinForce/Torquerolloutandspecifythevalueas5000.

•SelectthefaceofthemodelasshowninFigure-5.

Figure-5.Faceofmodeltobeselected


ApplyingGlobalDamping•ClickontheGlobalDamping button in theRibbon. TheGlobalDampingPropertyManagerwillbedisplayed;refertoFigure-6.

Figure-6.GlobalDampingPropertyManager

•SpecifythemodaldampingratiointhecellunderDampingRatioscolumnin the table or click on theRayleigh damping radio button and specifythedesiredparametersintheeditboxesdisplayed.



Modelingarea;refertoFigure-7.

Figure-7.Result

•YoumayneedtodeselecttheDeformedResultbuttonfromtheRibbontocheckthenon-deformedresult;refertoFigure-8.

Figure-8.DeformedResultbutton

Youcaninterprettheresultsasdiscussedinearlierchapters.

MODALTIMEHISTORYANALYSISAsdiscussedearlier,ModalTimeHistoryanalysisisdonewhenyouknowthe

variationofloadwithrespecttotimeexplicitly.NotethatTimehasgood

relationwithFrequencywhichisFrequency=1/Time.So,wecandefinethe

changingloadwithrespecttotimeorFrequency.Theproceduretoperform

thisanalysisisgivennext.

Assumethatthereisaboltmountedonenginechamber.Now,youknowthatenginehaslittlebitteasingnaturewhenitisstarted.So,theforceexertedonboltisvaryingwithtime.ThecompleteparametersofstudyaregiveninFigure-9.WeneedtofindouttheStressinducedinthebolt.

Figure-9.ParametersforModalTimeHistorystudy

StartingModalTimeHistoryAnalysis•Openthepartonwhichyouwanttoperformtheanalysis.




• Click on theLinearDynamic button and then on theModalTimeHistorybuttonfromtheOptionsrollout;refertoFigure-10.

Figure-10.ModalTimeHistorybutton

•ClickontheOKbuttonfromthePropertyManager.TheoptionsrelatedtoModalTimeHistoryAnalysiswillbedisplayed.

ApplyingMaterialandFixture•ClickontheApplyMaterialbuttonfromtheRibbonandselecttheAlloySteelmaterialfromtheMaterialdialogboxdisplayed.

•ClickontheApplybuttonandthenClosebuttonfromtheMaterialdialogbox.

•ClickonthedownarrowbelowFixturesAdvisorbuttonintheRibbonandselect the Fixed Geometry button. The Fixture PropertyManager will be

displayed.

•SelecttheroundbottomfaceoftheboltasshowninFigure-11.

Figure-11.Fixedroundface

•ClickontheOKbuttonfromthePropertyManagertoapplyfixture.

ApplyingHarmonicForce•ClickonthedownarrowbelowExternalLoadsAdvisorbuttonintheRibbon.Listoftoolswillbedisplayed.


•SelecttheflatfaceoftheboltasshowninFigure-12.

Figure-12.Faceselectedforapplyingforce

•ClickintheForceValueeditboxinthePropertyManagerandspecifythevalueas50N.

•SelecttheCurveradiobuttonfromtheVariationwithTimerolloutinthePropertyManagerandclickontheEditbutton.TheTimeCurvedialogboxwillbedisplayed.

•SelectHarmonicLoadingoptionfromtheShapedrop-downandspecifytheparametersasshowninFigure-13.SpecifytheStarttimeandEndtimeas0and1respectively,inthedialogbox.

Figure-13.ParametersforTimecurve

•ClickontheOKbuttonfromthedialogboxtoapplytheHarmoniccurve.


RunningtheAnalysisClickontheRunThisStudybuttonfromtheRibbontoseethemagic.StressresultwillbedisplayedasshowninFigure-14.Youalreadyknowtherest

of story about generating other reports like Modal Shape Plot, Frequency

ResponsePlot,andsoon.

Figure-14.Stressreport

In the above analysis, we have seen the effect of vibration on the bolt

during starting of engine. We find that the stress induced is well below

theYieldStrength.But,thejourneyofbolthasnotendedhere.Now,the

bolt has to sustain the continuous harmonic loading due to vibrations of

enginebecauseJimmyisgoingtoNewYorkridinghisbike.

HARMONICANALYSISNow, we have a range of frequency under which the bolt is going to work

duringhiscoursetoNewYork,say0Hzto5000Hz.Notethattheremightbe natural frequencies of bolt in this range which can be dangerous for

Jimmy’ssafety.Let’sseewhetherJimmywillreachNewYorkornot.

StartingHarmonicAnalysis•Openthepartonwhichyouwanttoperformtheanalysis.




•ClickontheLinearDynamicbuttonandthenontheHarmonicbuttonfromtheOptionsrollout;refertoFigure-15.

Figure-15.HarmonicStudybutton

•ClickontheOKbuttonfromthePropertyManager.TheoptionsrelatedtoHarmonicAnalysiswillbedisplayed.

ApplyingMaterialandFixture•ClickontheApplyMaterialbuttonfromtheRibbonandselecttheAlloySteelmaterialfromtheMaterialdialogboxdisplayed.



displayed.

•SelecttheroundbottomfaceoftheboltasshowninFigure-16.

Figure-16.Fixedroundface


ApplyingForce•ClickonthedownarrowbelowExternalLoadsAdvisorbuttonintheRibbon.Listoftoolswillbedisplayed.


•SelecttheflatfaceoftheboltasshowninFigure-17.

Figure-17.Faceselectedforapplyingforce

•ClickintheForceValueeditboxinthePropertyManagerandspecifythevalueas50N.

•ClickinthePhaseAngleeditboxinPhaseAnglerolloutifyouwanttospecifyphaseangle.(Wehavekeptitzero.Remembertheformula;P=A

sin(ωt+φ)whereφisphaseangle).


SettingFrequencyRange• Right-click on the Harmonic study from theAnalysisManager and selectthe Properties option from the shortcut menu; refer to Figure-18. The

Harmonicdialogboxwillbedisplayed;refertoFigure-19.

Figure-18.Propertiesoption

Figure-19.Harmonicdialogbox

•Specifythenumberoffrequenciestobetestedto10byusingtheNumberoffrequenciesspinnerintheOptionsareaofthedialogbox.

•ClickontheHarmonicoptionstabandspecifytheUpperlimitas5000Hz;refertoFigure-20.

Figure-20.Upperlimitforfrequencies


Jimmyreachesornot(RunningAnalysis)•ClickontheRunThisStudybuttonfromtheRibbonandwait&watch.TheStressresultwillbedisplayedasshowninFigure-21whichconcludesthat

nobody can stop Jimmy. The stress in bolt is well below the yield

strength.

Figure-21.ResultofHarmonicstudy

There are some situations where you need to see the effect of base

excitationontheobject.Insuchcases,youmightberequiredtoperform

theResponseSpectrumanalysis.Theprocessisgivennext.

RESPONSESPECTRUMANALYSISLet me tell you that Jimmy placed his camera in the side box of his

motorbikebymistakeandthecamerahasexperiencedallthejerksprovided

byroad.Let’sseewhathappenstothebodyofhisnewcamera.Assumethat

theexcitationcausedoncamerabodyis2m/s2.

StartingResponseSpectrumAnalysis•Openthepartonwhichyouwanttoperformtheanalysis(obviouslycamera

body!!).

•ClickonthedownarrowbelowtheStudyAdvisorbuttonandselecttheNewStudy tool from the drop-down. List of analysis studies that can be


• Click on theLinearDynamic button and then on theResponse SpectrumAnalysisbuttonfromtheOptionsrollout;refertoFigure-22.

Figure-22.ResponseSpectrumAnalysisbutton

•ClickontheOKbuttonfromthePropertyManager.TheoptionsrelatedtoResponseSpectrumAnalysiswillbedisplayed.

ApplyingMaterialandFixture•ClickontheApplyMaterialbuttonfromtheRibbonandselecttheAcrylic(Medium-highimpact)plasticfromtheMaterialdialogboxdisplayed;refertoFigure-23.

Figure-23.Materialdialogboxwithplasticmaterials



displayed.

•SelectthebottomfaceofthecameraasshowninFigure-24.

Figure-24.Bottomfaceofcamerabodyselected


ApplyingExcitationNosir!Excitationisnotlinkedwithhumanemotionshere.Excitationisa

displacement, velocity, or acceleration caused in the body due to

vibrations. There are two tools available to define excitation; refer to

Figure-25.

Figure-25.Excitationtools

If you have specified base at more than one faces then you can use the

SelectedBaseExcitationtooltospecifyexcitationforindividualbases.Tospecify the same excitation for all the bases, use the Uniform BaseExcitationtool.

•ClickonthedownarrowbelowExternalLoadsAdvisorbuttonintheRibbon.Listoftoolswillbedisplayed.

•ClickontheUniformBaseExcitationtoolfromthelist.TheUniformBaseExcitationPropertyManagerwillbedisplayed.

•SelecttheAccelerationradiobuttonfromtheTyperolloutandspecify2inverticaldirection;refertoFigure-26.

Figure-26.UniformBaseExcitationPropertyManager


excitation.

Nowwearereadyforthemagic.ClickontheRunThisStudybuttonfromtheRibbonandseewhetherthecameraisinonepieceormorepieces;refertoFigure-27.

Figure-27.ResultofResponseSpectrum

Even if you change the value of Base excitation to 20000 m/s2, still the

camerawillbesafe.Becausethepowerofacrylicplasticwillnotletyou

down.Thisplasticisusedtomakebulletproofshields.

PRACTICE1

In the below problem, you will analyze a driving shaft of automobile for

itsabilitytosustainthetorqueprovidedbyengine.Notethatthedriver

ofthisvehicleisrashdriverandhereallydon’tcareabouthismachine.

So,youmightneedtoperformtherandomvibrationanalysis.Theparameters

for the analysis are given in Figure-28. The model of this problem is

availableinresourcekit.

Figure-28.Parametersforanalysis

SELF-ASSESSMENT

Q1.Staticstudiesassumethatloadsareconstantorappliedataninstant.

(T/F)

Q2.Generallyifthefrequencyofaloadislargerthan1/3ofthelowest

(fundamental)frequencyofobject,adynamicstudyshouldbeused.(T/F)

Q3.Aviscousdamper(ordashpot)generatesaforcethatisproportionalto

mass.(T/F)

Q4.CriticaldampingCcistheleastamountofdampingthatcausesasystem

toreturntoitsequilibriumpositionwithoutoscillating.(T/F)

Q5. If the part has softer elements then Rayleigh Damping can product

unrealisticresultsbecauseofstiffnessmatrixpart.(T/F)

Q6. Which of the following dynamic analysis should be used to find out

stresswhenvariationofeachloadwithtimeisknownexplicitly?

a.ModalTimeHistoryAnalysis

b.HarmonicAnalysis

c.RandomVibrationAnalysis

d.ResponseSpectrumAnalysis

Q7.Whichofthefollowingdynamicanalysisshouldbeusedtocalculatethe

peaksteadystateresponseduetoharmonicloadsorbaseexcitations.


b.HarmonicAnalysis



Q8.Whichofthefollowingdynamicanalysisshouldbeusedtocalculatethe

responseduetonon-deterministicloads.


b.HarmonicAnalysis



Q9.Inarandomvibrationstudy,loadsaredescribedstatisticallyby…………

functions.

Q10. A displacement, velocity, or acceleration caused in the body due to

vibrationsiscalled…………..

ThermalAnalysis

Chapter9

TopicsCovered


•Introduction

•TypesofThermalAnalysis

•StartingThermalAnalysis.


•DefiningFixtures

•Applyingloads




INTRODUCTIONThermalanalysisisamethodtocheckthedistributionofheatoverabody

duetoappliedthermalloads.Notethatthermalenergyisdynamicinnature

andisalwaysflowingthroughvariousmediums.Therearethreemechanisms

bywhichthethermalenergyflows:

•Conduction

•Convection

•Radiation

In all three mechanisms, heat energy flows from the medium with higher

temperature to the medium with lower temperature. Heat transfer by

conduction and convection requires the presence of an intervening medium

whileheattransferbyradiationdoesnot.

Theoutputfromathermalanalysiscanbegivenby:

1.Temperaturedistribution.

2.Amountofheatlossorgain.

3.Thermalgradients.

4.Thermalfluxes.

This analysis is used in many engineering industries such as automobile,

piping,electronic,powergeneration,andsoon.

ImportanttermsrelatedtoThermalAnalysisBeforeconductingthermalanalysis,youshouldbefamiliarwiththebasic

conceptsandterminologiesofthermalanalysis.Followingaresomeofthe

importanttermsusedinthermalanalysis:

HeatTransferModesWheneverthereisadifferenceintemperaturebetweentwobodies,theheat

istransferredfromonebodytoanother.Basically,heatistransferredin

threeways:Conduction,

Convection,andRadiation.

Conduction

In conduction, the heat is transferred by interactions of atoms or

moleculesofthematerial.

For example, if you heat up a metal rod at one end, the heat will be

transferredtotheotherendbytheatomsormoleculesofthemetalrod.

ConvectionInconvection,theheatistransferredbytheflowingfluid.Thefluidcan

begasorliquid.Heatingupwaterusinganelectricwaterheaterisagood

exampleofheatconvection.Inthiscase,watertakesheatfromtheheater.

RadiationIn radiation, the heat is transferred in space without any matter.

Radiationistheonlyheattransfermethodthattakesplaceinspace.Heat

comingfromtheSunisagoodexampleofradiation.TheheatfromtheSun

istransferredtotheearththroughradiation.

ThermalGradientThethermalgradientistherateofincreaseintemperatureperunitdepth

inamaterial.

ThermalFluxTheThermalfluxisdefinedastherateofheattransferperunitcross-

sectionalarea.Itisdenotedbyq.

BulkTemperatureIt is the temperature of a fluid flowing outside the material. It is

denotedbyTb.TheBulktemperatureisusedinconvectiveheattransfer.

FilmCoefficientItisameasureoftheheattransferthroughanairfilm.

EmissivityThe emissivity of a material is the ratio of energy radiated by the

material to the energy radiated by a black body at the same temperature.

Emissivity is the measure of a material’s ability to absorb and radiate

heat.Itisdenotedbye.Emissivityisanumericalvaluewithoutanyunit.

Foraperfectblackbody,e=1.Foranyothermaterial,e<1.

Stefan–BoltzmannConstant

Theenergyradiatedbyablackbodyperunitareaperunittimedividedby

thefourthpowerofthebody’stemperatureisknownastheStefan-Boltzmann

constant.Itisdenotedbys.

ThermalConductivityThethermalconductivityisthepropertyofamaterialthatindicatesits

abilitytoconductheat.ItisdenotedbyK.

SpecificHeatThespecificheatistheamountofheatrequiredperunitmasstoraisethe

temperatureofthebodybyonedegreeCelsius.Itisdenotedbyc.

THERMALLOADSTostartthethermalanalysis,clickonthedownarrowbelowStudyAdvisor.Select the New Study button from the tools displayed. The StudyPropertyManagerwillbedisplayed.ClickontheThermal button from theType rollout and click on theOK button from thePropertyManager. Thetools related to thermal analysis will be displayed. Before performing

thermal analysis, we will get familiar with various options required

specifically for thermal analysis. One of the major player in thermal

analysis is the thermal load. To apply the thermal loads, options are

availableintheThermalLoadsdrop-down;refertoFigure-1.Theoptionsinthisdrop-downarediscussednext.

Figure-1.ThermalLoadsdrop-down

TemperatureTheTemperaturetoolisusedtospecifytemperatureofselectedface/faces.Toapplytemperaturefollowthestepsgivennext.

•ClickontheTemperaturetoolfromthelistoftoolsdisplayedonclickdown arrow below Thermal Loads in the Ribbon. The TemperaturePropertyManagerwillbedisplayedasshowninFigure-2.

Figure-2.TemperaturePropertyManager

•Selectthefaceonwhichyouwanttosetthetemperature.

•ClickintheTemperatureeditboxandspecifythedesiredvalue.• If you want to change the unit of temperature from the default Kelvin

unit,thenclickontheKelvin(K)optionnexttoTemperatureeditbox.Thelistofoptionsrelatedtotemperatureunitswillbedisplayed.

•Selectthedesiredunitfromthelist.

• If you are performing the transient thermal study, then the Initialtemperatureradiobuttonwillbeactive;refertoFigure-3.

Figure-3.TemperaturePropertyManagerfortransientstudy

HowtostartTransientThermalAnalysis?Afterstartingthethermalanalysis,right-clickontheanalysisnameintheAnalysisManager;refertoFigure-4.Theoptionsrelatedtoanalysiswillbedisplayedintheshortcutmenu.

SelectthePropertiesoptionfromthemenu.TheThermaldialogboxwillbedisplayed; refer to Figure-5. Select theTransient radio button from theSolutionTypeareaofthedialogbox.Theoptionsrelatedtoanalysistimewill be displayed. Set the desired time duration and increment for the

analysisbyusingtheeditboxes.Theotheroptionsinthisdialogboxhave

alreadybeendiscussedinpreviouschapters.ClickontheOKbuttonfrom

thedialogboxtoapplythesettings.

Figure-4.AnalysisPropertiesshortcutmenu

Figure-5.Thermaldialogbox

•Usingthisoption,youcanspecifythestartingtemperatureoftheface.

Although,itwillchangeautomaticallyundertheapplicationofheatflux.

Youwilllearnmoreaboutthistoollaterwhileperformingtheanalysis.

•IfyouselecttheTemperatureradiobuttonforatransientthermalstudythen the Variation with Time rollout is also displayed in the


Figure-6.TemperaturePropertyManagerwithtimevaryingtemperature

•TheoptionsintheVariationwithTimerolloutaresameasdiscussedinpreviouschapters.

•Ifyouwanttoselecttheallexposedfacesofthemodel,thenclickon

theSelectallexposedfacesbuttonfromthePropertyManager.


dialogbox.

ConvectionConvectionisthephenomenabywhichheatistransferredthroughamedium

likeair,fluidorsolid.Everymediumhasitslimitationtotransferthe

heat energy. This limitation is mathematically represented by ConvectionHeatcoefficientQconvection.

Qconvection=hA(Ts-Tf)

Here,hisheattransfercoefficienthasunitW/m2.k

Tsisthetemperatureofthesurface.

Tfisthetemperatureofthesurroundingfluid.

Aistheareaofsurface.

InSolidWorksSimulation,weneedtospecifytheQconvectionfor the convection

phenomena.Thestepstoapplytheheatconvectionaregivennext.

• Click on the down arrow below theThermal Loads from theRibbon. Thelistoftoolswillbedisplayed.

• Select the Convection button from the list of tools. The ConvectionPropertyManagerwillbedisplayedasshowninFigure-7.

Figure-7.ConvectionPropertyManager

•Selectthefacefromwhichtheconvectionisoccurring.

•ClickintheConvectionCoefficienteditboxintheConvectionCoefficientrolloutandspecifythedesiredvalueinit.

• Click in the Bulk Ambient Temperature edit box in the Bulk AmbientTemperature rollout and specify the surrounding temperature for the

analysis.


PropertyManagertoapplytheheatconvection.

HeatPowerThisistheenergyappliedontheselectedfaceintheformofheat.You

can specify the heat power applied on the face by using theHeat Powerbutton.Thestepstousethisbuttonaregivennext.

•ClickonthedownarrowbelowtheThermalLoadsbuttonintheRibbon.Thelistoftoolswillbedisplayed.

• Click on the Heat Power button from the list. The Heat PowerPropertyManagerwillbedisplayed;refertoFigure-8.

•Selectthefaceonwhichyouwanttoapplytheheat.

• Click in the Heat Power edit box in the Heat Power rollout in

PropertyManagerandspecifythedesiredvalueofheatpower.• If you are performing transient thermal study then you can apply a

thermostatconditionbyselectthecheckboxontheThermostat (Transient)rollout.

•OnselectingthecheckboxofThermostat(Transient)rollout,theexpandedrolloutisdisplayed;refertoFigure-9.

Figure-8.HeatPowerPropertyManager

Figure-9.Thermostatrollout

•Clickinthepinkselectionboxintherolloutandselectthevertexthat

youwanttoselectasasensorforthethermostat.

•Inthefirsteditboxbelowthepinkselectionbox,youcanspecifythe

minimumtemperatureforstartinguptheheatpower.

•Inthenexteditbox,youcanspecifythemaximumtemperatureuptowhich

thepowersourcewillprovidetheheat.


PropertyManager.

HeatFluxHeatfluxistheheatenergyappliedperunitareaoftheselectedface.

Thestepstoapplyheatfluxonthemodelaregivennext.

•ClickonthedownarrowbelowThermalLoadsbuttonintheRibbon. Thelistoftoolswillbedisplayed.

• Click on the Heat Flux button from the list. The Heat FluxPropertyManagerwillbedisplayedasshowninFigure-10.

Figure-10.HeatFluxPropertyManager

• The options in this PropertyManager are same as in Heat PowerPropertyManagerandcanbeusedinthesameway.

RadiationThermal radiation is the thermal energy emitted by bodies in the form of

electromagnetic waves because of their temperature. All bodies with

temperatures above the absolute zero emit thermal energy. Because

electromagnetic waves travel in vacuum, no medium is necessary for

radiation to take place. Thermal radiation can occur between ambienttemperaturesurroundingandsurfaceofbodyorbetweensurfaceofonebodyandsurfaceofotherbody.Thestepstospecifyradiationaregivennext.

•ClickondownarrowbelowThermalLoadsbutton.Thelistoftoolswillbedisplayed.

• Click on the Radiation button from the list. The RadiationPropertyManagerwillbedisplayedasshowninFigure-11.

Figure-11.RadiationPropertyManager

•Selectthefacefromwhichtheradiationisoccurring.

• Click in the first edit box in the Radiation Parameters rollout and

specifytheambienttemperatureifyouhaveselectedtheSurfacetoambientradiobuttonfromtheTyperollout.

• If you have selected the Surface to surface radio button from the Typerollout and selected the Open system check box from the RadiationParametersrolloutthenalsoyoucanspecifytheambienttemperatureinthefirsteditboxintheRadiationParametersrollout.

•ClickintheEmissivityeditboxandspecifytheemissioncoefficientforradiation.


PropertyManager.

CONTACTSETWehaveusedconnectionsbetweenvariouspartsofassemblywhileperforming

structural analyses. In the same way, we are also required to specify

connections between various parts of assembly in terms of thermal

properties.Forthermalanalyses,wecanspecifythefollowingconnections:

•ThermalResistance

•Bonded

•Insulated

The tools to specify these connections are available in the ConnectionsAdvisor drop-down. Click on theContact Set tool from the drop-down. TheContactSetsPropertyManagerwillbedisplayedasshowninFigure-12.

Selectthedesiredcontacttypefromthedrop-downintheTyperolloutandselectthefacestoapplythethermalcontacttype.Inthesameway,you

canusetheComponentContactbuttontoapplytheconnectionbetweentwoparts.

ThermalResistanceContactThe thermal resistance contact is used to specify thermal resistance

betweentwocomponentsconnectedinassembly.Onselectingthisoption,the

PropertyManager is displayed as shown in Figure-12. Select the two

contactingfacesofthecomponentsinassemblybyusingtheselectionboxes

inthePropertyManager. Specify the desired value of thermal resistance.TheunitofthermalresistanceisK/W.

BondedContactThe bonded contact is used when there is perfect heat conduction between

twocontactingparts.Notethattheheatflowbetweenpartswilldependon

theirthermalconductance.


InsulatedContactThe insulated contact is same as No penetration in structural analysis.

This contact is used when there is no heat conduction between the two

contactingparts.

PRACTICALONSTEADYSTATETHERMALANALYSIS

Inthistutorial,wewillperformasteadystatethermalanalysisonareal

worldmodelandcheckthedistributionoftemperature/heatoverthesurface

of the model. Note that model for this practical is available in the

resourcekit.

Startingtheanalysis•Openthepartonwhichyouwanttoperformtheanalysis.




• Click on the Thermal button then click on the OK button from the

PropertyManager.Thetoolsrelatedtothermalanalysiswillbedisplayed.

ApplyingMaterial•ClickontheApplyMaterialbuttonfromtheRibbon.TheMaterial dialogboxwillbedisplayed.

•ExpandtheSolidWorksMaterialsnodeandthentheAluminiumAlloysnodeintheleftofthedialogbox.

• Browse through the materials and select theC355.0-T61 PermanentMoldcast(SS)material;refertoFigure-13.

• Click on theApply button and then click on theClose button from thedialogboxtoexitthedialogbox.


Applyingconvectiontothemodel• Click on the down arrow below Thermal Loads button and select the

Convectionbuttonfromthelist.TheTemperaturePropertyManagerwillbedisplayedasshowninFigure-14.

Figure-14.ConvectionPropertyManager

•SelectalltheinnerfacesofthemodelasshowninFigure-15.

Figure-15.Facesofmodeltobeselected

•Specifytheconvectioncoefficientas10000intheConvectionCoefficient

edit box inPropertyManager. This convection coefficient is for engineoil.

•ClickinBulkAmbientTemperatureeditboxinthePropertyManager andspecifythevalueas400K.


convection.

Applyingheatgeneratedbygascombustionontheheadofthepiston

•ClickonthedownarrowofThermalLoadsintheRibbonandselecttheHeat Power button from the list displayed. The Heat PowerPropertyManagerwillbedisplayed;refertoFigure-16.

Figure-16.HeatPowerPropertyManager

•ClickontheTotalradiobuttonintheSelectedEntitiesrollout.•SelecttheheadfacesofthepistonasshowninFigure-17.

Figure-17.Facestobeselected

•ClickintheHeatPowereditboxintheHeatPowerrollout.Specifythetotalheatpoweras20000.

•ClickontheOKbuttonfromthePropertyManagertoapplytheheat.

RunningtheAnalysis•ClickontheRunbuttonfromtheRibbon.Theanalyzingofproblemwillstart.

• After the analysis is complete. The solution of the analysis will be


Figure-18.Solutionofanalysis

•Tochangethetemperaturescale,right-clickontheTemperaturescaleat

theright.Ashortcutmenuwillbedisplayed;refertoFigure-19.

Figure-19.Shortcutmenufortemperaturescale

• Click on the Settings button from the shortcut menu. The Thermal PlotPropertyManagerwillbedisplayed;refertoFigure-20.

•ClickontheDefinitiontabandthenclickontheseconddrop-downintheDisplayrollout;refertoFigure-21.

Figure-20.ThermalPlotPropertyManager

Figure-21.DefinitiontabofThermalPlotPropertyManager

•ClickontheCelsiusoptionfromthelistdisplayedandclickontheOKbuttonfromthePropertyManager.ThescalewillchangetoCelsius.

•YoucanselecttheothercomponentsofThermalanalysisbyright-clicking

ontheTemperaturescaleandselectingthedesiredoptionfromtheThermalComponentcascadingmenu;refertoFigure-22.

Figure-22.ThermalComponents

SWITCHINGFROMSTEADYSTATEANALYSISTOTRANSIENTTHERMALANALYSIS

Earlier,wehaveperformedthesteadystateanalysis.Now,wewillusethe

aboveanalysisandswitchtotransientthermalanalysis.Theprocedureto

switchtotransientthermalanalysisisgivennext.

• Right-click on the name of analysis in theAnalysisManager; refer toFigure-23.

• Click on the Properties button from the menu displayed. The Thermaldialogboxwillbedisplayed;refertoFigure-24.

Figure-23.Shortcutmenuforanalysisproperties

Figure-24.Thermaldialogbox

•ClickontheTransientradiobutton.Theeditboxesbelowitwillbecomeactive.

•Specifythetotaltimeofstudy(inseconds)intheTotaltimeeditboxas10seconds.

•ClickintheTimeincrementeditboxandspecifytheincrementvalueinsecondsas1.

•Ifyouhaveearlierperformedanyotheranalysisfromwhereyouwantto

import the temperature as the initial value then click on the Initialtemperature from thermal study check box and then select the study namefromthedrop-down.

•Youcanalsoselectthedesiredstepnumberfromtheadjacentspinner.

•SelectthedesiredsolverfromtheSolverareaofthedialogboxandthenclickontheOKbuttonfromthedialogbox.

SpecifyingInitialTemperatureNow,weneedtospecifytheinitialtemperaturefortheanalysisifwehave

notimporteditfromanyearlierstudy.

• Click on theTemperature button from theThermalLoads drop-down. TheTemperaturePropertyManagerwillbedisplayed.

• Select the Initial Temperature radio button and select all the faces byusingSelectallexposedfacesbuttonasshowninFigure-25.

Figure-25.Facestobeselectedforinitialtemperature

• Click in theTemperature edit box and in theTemperature rollout andspecifythevalueas25°C.


temperature.

Runningtheanalysis•ClickontheRunbuttontoruntheanalysis.• After the analysis is complete, compare the two results. You will find

thattheanalysistemperaturerangeischangingandthepartisdisplayed

cooler than earlier one. This is because we have allowed the time for

cooling in analysis and we have specified the initial temperature as

25°C.•Whenyouanimatetheresult,wewillfindthatheatistransferredfrom

topfacetosidewallsasthetimepasses.

UsingProbetofindouttemperature•Afterrunningtheanalysis,right-clickinthemodelingarea.Ashortcut

menuwillbedisplayed.

•SelecttheProbebuttonfromtheshortcutmenu;refertoFigure-26.

Figure-26.Probebutton

•TheProbeResultPropertyManagerwillbedisplayed;refertoFigure-27.Figure-27.ProbeResultPropertyManager

• Click on the model at the desired position. The temperature and other

parametersoftheselectedpositionwillbedisplayedinaboxandResultsrolloutofPropertyManager;refertoFigure-28.

Figure-28.Temperatureoutput

• Click on the Plot button from the Report Options rollout of the

PropertyManagertocheckthegraphoftemperaturechange.

Note that to be able to perform the analysis using the SolidWorks

Simulationsoftware,youshouldbeabletoanswerthefollowingquestions:

1.Heattransferthroughasolidbodyisreferredtoas

oConductionoConvectionoRadiationoGeneration

2.Thetemperaturegradientisdefinedas

oTemperaturerateofchangeperunitlength

oHeatflowthroughabody

oTemperaturerateofchangeperunitvolume

oTemperaturerateofchangeperunitarea

3.Heatfluxisdefinedby

oTheamountofheatgeneratedperunitvolume

oTheheattransferrateperunitarea

oTheamountofheatstoredinacontrolvolume

oThetemperaturechangeperunitlength

4.Heattransferbetweenasolidbodyandafluidisreferredtoas

oConductionoConvectionoRadiationoGeneration

5.Which behavior best describes a material with a high thermal conductivitycomparedtoamaterialwillasmallerthermalconductivity?

oTemperaturechangeissmallerthroughthesolid

oHeatfluxishigherthroughthesolid

oThermalresistanceislowerthroughthesolid

oAlloftheabove

6.Theconvectioncoefficientisrelatedto

oTheratethatheatistransferredbetweenasolidandfluid

oTheratethatheatistransferredbetweentwosolids

oTheemissivepowerofthematerial

oTheheatgenerationcapabilityofthematerial

7.Theamountofheattransferredbyradiationisdirectlyrelatedto

oTheStephan-Boltzmannconstant

oThesurfacetemperature

oTheemissivityofthematerial

oAlloftheabove

8.Ifnoheatistransferredtoorfromasurface,itisreferredtoas

oIsothermaloExothermaloAdiabaticoIsobaric

9.Whenalltemperaturesareinequilibrium,theproblemisassumedtobe

oTransient

oSteady-State

oLaminar

oNoneoftheabove

10.Whichofthefollowingtermsisnotpartoftheenergybalanceforheattransfer?

oGeneratedenergy

oStoredenergy

oEnergyintothesystem

oEnergydestroyed

*********************************************************

PROBLEM1

Ametalsphereofdiameterd=35mmisinitiallyattemperatureTi=700K.

Att=0,thesphereisplacedinafluidenvironmentthathaspropertiesof

T∞=300Kandh=50W/m2-K.Thepropertiesofthesteelarek=35W/m-K,

ρ = 7500 kg/m3, and c = 550 J/kg-K. Find the surface temperature of the

sphereafter500seconds.

PROBLEM2

Aflangedpipeassembly;refertoFigure-29,madeofplaincarbonsteelis

subjected to both convective and conductive boundary conditions. Fluid

inside the pipe is at a temperature of 130°C and has a convection

coefficientofhi=160W/m2-K.Airontheoutsideofthepipeisat20°C

andhasaconvectioncoefficientofho=70W/m2-K.Therightandleftends

ofthepipeareattemperaturesof450°Cand80°C,respectively.Thereisa

thermal resistance between the two flanges of 0.002 K-m2/W. Use thermal

analysis to analyze the pipe under both steady state and transient

conditions.

Figure-29.Flangedpipeassembly

BucklingAnalysis

Chapter10

TopicsCovered


•Introduction

•StartingBucklingAnalysis.


•DefiningFixtures

•Applyingloads




INTRODUCTIONSlendermodelstendtobuckleunderaxialloading.Bucklingisdefinedas

thesuddendeformationwhichoccurswhenthestoredmembrane(axial)energy

isconvertedintobendingenergywithnochangeintheexternallyapplied

loads. Mathematically, when buckling occurs, the stiffness becomes

singular.TheLinearizedbucklingapproach,usedhere,solvesaneigenvalue

problem to estimate the critical buckling factors and the associated

bucklingmodeshapes.

Amodelcanbuckleindifferentshapesunderdifferentlevelsofloading.

Theshapethemodeltakeswhilebucklingiscalledthebucklingmodeshape

andtheloadingiscalledthecriticalorbucklingload.Bucklinganalysis

calculatesanumberofmodesasrequestedintheBucklingdialog.Designers

areusuallyinterestedinthelowestmode(mode1)becauseitisassociated

withthelowestcriticalload.Whenbucklingisthecriticaldesignfactor,

calculatingmultiplebucklingmodeshelpsinlocatingtheweakareasofthe

model.Themodeshapescanhelpyoumodifythemodelorthesupportsystem

topreventbucklinginacertainmode.

A more vigorous approach to study the behavior of models at and beyond

bucklingrequirestheuseofnonlineardesignanalysiscodes.

Inalaymen’slanguage,ifyoupressdownonanemptysoftdrinkcanwith

yourhand,notmuchwillseemtohappen.Ifyouputthecanonthefloor

andgraduallyincreasetheforcebysteppingdownonitwithyourfoot,at

some point it will suddenly squash. This sudden scrunching is known as

“buckling.”

Modelswiththinpartstendtobuckleunderaxialloading.Bucklingcanbe

defined as the sudden deformation, which occurs when the stored membrane

(axial) energy is converted into bending energy with no change in the

externally applied loads. Mathematically, when buckling occurs, the total

stiffnessmatrixbecomessingular.

In the normal use of most products, buckling can be catastrophic if it

occurs.Thefailureisnotonebecauseofstressbutgeometricstability.

Oncethegeometryofthepartstartstodeform,itcannolongersupport

even a fraction of the force initially applied. The worst part about

buckling for engineers is that buckling usually occurs at relatively low

stressvaluesforwhatthematerialcanwithstand.Sotheyhavetomakea

separatechecktoseeifaproductorpartthereofisokaywithrespectto

buckling.

Slender structures and structures with slender parts loaded in the axial

direction buckle under relatively small axial loads. Such structures may

fail in buckling while their stresses are far below critical levels. For

suchstructures,thebucklingloadbecomesacriticaldesignfactor.Stocky

structures, on the other hand, require large loads to buckle, therefore

bucklinganalysisisusuallynotrequired.

Bucklingalmostalwaysinvolvescompression.Incivilengineering,buckling

is to be avoided when designing support columns, load bearing walls and

sectionsofbridgeswhichmayflexunderload.ForexampleanI-beammaybe

perfectly

“safe”whenconsideringonlythemaximumstress,butfaildisastrouslyif

justonelocalspotofaflangeshouldbuckle!Inmechanicalengineering,

designs involving thin parts in flexible structures like airplanes and

automobiles are susceptible to buckling. Even though stress can be very

low,bucklingoflocalareascancausethewholestructuretocollapsebya

rapidseriesof‘propagatingbuckling’.

Buckling analysis calculates the smallest (critical) loading required for

buckling a model. Buckling loads are associated with buckling modes.

Designers are usually interested in the lowest mode because it is

associated with the lowest critical load. When buckling is the critical

design factor, calculating multiple buckling modes helps in locating the

weakareasofthemodel.Thismaypreventtheoccurrenceoflowerbuckling

modesbysimplemodifications.

USEOFBUCKLINGANALYSISSlenderpartsandassemblieswithslendercomponentsthatareloadedinthe

axialdirectionbuckleunderrelativelysmallaxialloads.Suchstructures

canfailduetobucklingwhilethestressesarefarbelowcriticallevels.

For such structures, the buckling load becomes a critical design factor.

Bucklinganalysisisusuallynotrequiredforbulkystructuresasfailure

occursearlierduetohighstresses.Theproceduretousebucklinganalysis

inSolidWorksSimulationisgivennext.

StartingtheBucklingAnalysis•Openthepartonwhichyouwanttoperformtheanalysis.




•ClickontheBucklingbutton.ThetoolsrelatedtobucklinganalysiswillbedisplayedintheRibbon.

SettingtheNumberofBucklingModes•ClickontheStudyPropertiestoolfromtheStudyAdvisordrop-downintheRibbon.TheBucklingdialogboxwillbedisplayedasshowninFigure-1.

• Specify the desired number of buckling modes in theNumber of bucklingmodesspinnerinthedialogbox.

•ClickontheOKbuttonfromthedialogboxtoapplythechanges.

Figure-1.Bucklingdialogbox

ApplyingMaterial•ClickontheApplyMaterialbuttonfromtheRibbon.TheMaterial dialogboxwillbedisplayed;refertoFigure-2.

•Selectthe1060AlloymaterialunderAluminiumAlloysnode.

• Click on the Apply button and then select the Close button from the

dialogbox.

ApplyingFixture•ClickonthedownarrowbelowFixturesAdvisorintheRibbon.Thelistoftoolswillbedisplayed.

• Click on the Fixed Geometry button from the list. The FixturePropertyManagerwillbedisplayed;refertoFigure-3.



•SelectthefaceasshowninFigure-4.

Figure-4.Faceforfixture


ApplyingtheForce• Click on the down arrow belowExternal Loads Advisor in theRibbon. Alistoftoolswillbedisplayed.

•ClickontheForcebuttonfromthelist.TheForce/TorquePropertyManagerwillbedisplayed;refertoFigure-5.


•SelectthefaceasshowninFigure-6.

•ClickintheForceValueeditboxinthePropertyManagerandspecifythevalueofforceas1000.

Figure-6.Faceforapplyingforce

•ClickontheOKbuttonfromthePropertyManagertoapplytheforces.

RunningtheAnalysis• Click on the Run button from the Ribbon. The analysis will start

solving.

• After the analyzing is complete, the result will be displayed in the

modelingarea;refertoFigure-7.

Figure-7.Result

•Fromtheabovefigure,youcancheckthattheloadfactorforthismodel

is2.7792.Thisloadfactorrepresentsthefactorofsafetyforthemodel.•Accordingtotheabovevalue,themodelisabletosustaintheloadfor

buckling.

• Note that although the part will not fail under the given load but it

willbedeformedasperthescalesoyoushouldalsocheckthenon-linear

staticanalysisresults.

MeaningofdifferentvaluesofloadfactoraregiveninFigure-8.

Figure-8.Bucklingloadfactor

SELF-ASSESSMENT

Q1. Once the geometry of the part starts to deform, it can no longer

supportevenafractionoftheforceinitiallyapplied.(T/F)

Q2.Bucklingoccursatrelativelylowstressvaluesforwhatthematerial

canwithstand.(T/F)

Q3. Buckling analysis is usually not required for bulky structures as

failureoccursearlierduetohighstresses.(T/F)

Q4.TheloadfactorinBucklinganalysisresultsrepresentsthefactorof

safetyforthemodel.(T/F)

Q5.Iftheloadfactoris1thenourmodelissafefrombuckling.(T/F)

FatigueAnalysis

Chapter11

TopicsCovered


•Introduction

•StartingFatigueAnalysis.

•Selectingthepreviousanalysis

•Definingthenumberofcycles



INTRODUCTIONRepeated loading and unloading weakens objects over time even when the

induced stresses are considerably less than the allowable stress limits.

This phenomenon is known as fatigue. Each cycle of stress fluctuation

weakens the object to some extent. After a number of cycles, the object

becomessoweakthatitfails.Fatigueistheprimecauseofthefailureof

manyobjects,especiallythosemadeofmetals.Examplesoffailuredueto

fatigue include, rotating machinery, bolts, airplane wings, consumer

products,offshoreplatforms,ships,vehicleaxles,bridges,andbones.

Linear and nonlinear structural studies do not predict failure due to

fatigue.Theycalculatetheresponseofadesignsubjectedtoaspecified

environment of restraints and loads. If the analysis assumptions are

observedandthecalculatedstressesarewithintheallowablelimits,they

concludethatthedesignissafeinthisenvironmentregardlessofhowmany

timestheloadisapplied.

Resultsofstatic,nonlinear,ortimehistorylineardynamicstudiescanbe

used as the basis for defining a fatigue study. The number of cycles

requiredforfatiguefailuretooccuratalocationdependsonthematerial

andthestressfluctuations.Thisinformation,foracertainmaterial,is

providedbyacurvecalledtheSNcurve.

StagesofFailureDuetoFatigueFailureduetofatigueoccursinthreestages:

Stage 1 One or more cracks develop in the material. Cracks can develop

anywhere in the material but usually occur on the boundary faces due to

higher stress fluctuations. Cracks can occur due to many reasons.

Imperfections in the microscopic structure of the materials and surface

scratchescausedbytoolingorhandlingaresomeofthem.

Stage2Someorallthecracksgrowasaresultofcontinuedloading.

Stage3Theabilityofthedesigntowithstandtheappliedloadscontinuetodeteriorateuntilfailureoccurs.

Fatigue cracks start on the surface of a material. Strengthening the

surfacesofthemodelincreasesthelifeofthemodelunderfatigueevents.

From the above theory, you can find out that the main player in Fatigue

analysisisthepropertiesofmaterialsrathertheS-Ncurves.

TheproceduretoperformtheFatigueanalysisisgivennext.

StartingFatigueAnalysis• Open a part on which you have already performed Static or dynamic

analysis.(WehaveopenedthefileusedinChapter3ofthisbook;refer

toFigure-1.)

Figure-1.Modelofchapter3

Figure-2.Variableamplitudehistorydatabutton

•ClickonthedownarrowbelowStudyAdvisor,thelistoftoolswillbedisplayed.

•ClickontheNewStudybuttonfromthelist.TheStudyPropertyManagerwillbedisplayed.

•ClickontheFatiguebuttonfromthelistandthenclickontheVariableamplitude history data button from the Options rollout of the


Note that in this example, we will study the Variable amplitude history

datafatiguestudybutinSolidWorkssimulation,wecanperformfourtype

offatigueanalysesviz.Constantamplitudeeventswithdefinedcycles,Variableamplitude history data, Harmonic- fatigue of sinusoidal loading, and Randomvibration-fatigue of random vibration. The procedure of all the studies is

almostthesame.

In case of Constant amplitude events with defined cycles, the load being

applied on the object is constant and we specify the number of loading

cyclestotestthefatigue.

IncaseofVariableamplitudehistorydata,theloadappliedonobjectvaries

withtime.Thisvariationcanbedefinedinthefatiguestudyitself.

IncaseofHarmonic-fatigueofsinusoidalloading,thedynamicloadisappliedintheformofsinusoidalcurve.Forthistypeoffatiguestudy,werequire

thedatafromstudiesperformedunderLinearDynamiccategory.

IncaseofRandomvibration-fatigueofrandomvibration,werequirethedatafromrandomvibrationstudy.Toperformthisstudy,youneedtoperformthe

randomvibrationstudyfirst.

• Note that if you want to study for a constant amplitude then you can

select the Constant amplitude events with defined cycles button from the

Optionsrollout.

•ClickontheOKbuttonfromthePropertyManagertostarttheanalysis.Thetoolsrelatedtofatigueanalysiswillbedisplayed;refertoFigure-

3.

Figure-3.Toolsforfatigueanalysis

InitiatingFatigueAnalysis•ClickonthedownarrowbelowFatigueintheRibbon.TheAddEventtoolwillbedisplayed.

• Click on theAdd Event tool. TheAdd Event (Variable) PropertyManagerwillbedisplayed;refertoFigure-4.

Figure-4.AddEventPropertyManager

•Bydefault,Static1studyisaddedintheeventlist.

•ClickintheNumberofrepeatsspinnerintheOptionsrolloutandspecifythe number of repetitions as300 for the load curve being generated inthenextsegment.

Now,weneedtospecifythetimecurveforthefatigueanalysis.

•ClickontheGetCurvebuttonfromthePropertyManager.TheLoadHistoryCurvedialogboxwillbedisplayed;refertoFigure-5.

Figure-5.LoadHistoryCurvedialogbox

•ClickintheNamefieldandspecifythedesirednameofthecurve.

•ClickontheTypedrop-downandselecttheTime&amplitudeoptionfromthelistdisplayed.

•ThetableoftimeversusamplitudeisdisplayedintheCurvedataarea.

•Double-clickonthe1buttonunderthePointcolumn.Thenextpointwillbeaddedinthetable;refertoFigure-6.

Figure-6.Curvedataafteraddingonemorepoint

•Similarly,youcanaddmorepoints.

•Enterthedatarelatedtoamplitudeinthetable;refertoFigure-7.

Figure-7.Curvedatatablewithcustomvalues


•ClickontheOKbuttonfromthePropertyManagertoaddtheevent.

ApplyingorEditingS-Ndata•Right-clickonthenameofthemodelintheAnalysisManagerandselecttheApply/EditFatiguedatabutton;refertoFigure-8.

Figure-8.ApplyEditFatigueDatabutton

•TheFatigueSNCurvestabinMaterialsdialogboxwillbedisplayed;refertoFigure-9.

Figure-9.FatigueSNCurvetabinMaterialsdialogbox

•Ifyouhavethetableofparametersthenspecifythedataasdoneincase

ofCurve Data. In this case, we will use the fatigue data of ASMEAusteniticSteel.

• Click on theDerive from material Elastic Modulus radio button from theSourceareainthedialogbox.Thedatawillbeimportedautomaticallyinthetable.

•ClickontheApplybuttonandthenClosebuttonfromthedialogbox.

ModifyingtheStaticAnalysisearlierperformed• Click on the Static 1 tab in the bottom bar of SolidWorks; refer to

Figure-10.Thestaticanalysiswillopen;refertoFigure-11.

Figure-10.Static1tab

Figure-11.Staticanalysisearlierperformed

•DoubleclickontheForce-1nodeintheAnalysisManager;refertoFigure-11.TheForce/TorquePropertyManagerwillbedisplayed.

•ChangetheforcevalueinthePropertyManagerto1800andclickontheOKbuttonfromthePropertyManager.

• Click on the Run This Study button from the Ribbon to update the

analysis.

RunningtheFatigueAnalysis• Click on theFatigue 1 tab from the bottom bar of SolidWorks. You willswitchbacktofatigueanalysis.

•ClickontheRunThisStudybuttonfromtheRibbon.

• Double-click on the Results2 (-Life-) node in the Analysis Manager. The

resultswillbedisplayedasshowninFigure-12.

Figure-12.Results

•Fromtheresults,wecanfindoutthatthepartwillfailon506thcycleatthelocationpaintedinred.

•Theredlocationisbelowthegreenmarkedarea,soyouneedtorotate

themodel;refertoFigure-13.

Figure-13.Locationinred

ChangingPropertiesofFatigueAnalysis•Right-clickontheFatigue1(-Default-)nodeintheAnalysisManager.Theoptionsrelatedtofatigueanalysiswillbedisplayed.

•ClickonthePropertiesbuttonfromthelistdisplayed.TheFatiguedialogboxwillbedisplayed;refertoFigure-14.

Figure-14.Fatiguedialogbox

•TheNo.ofBinsforrainflowcountingspinnerisusedtospecifythenumberofdivisionsofloadfrequencyforspecifiedamplitude.

• The options in the Computing alternating stress using area are used to

specifytheanalysisresulttobeusedfortestingfatigue.

• The options in the Mean stress correction area are used to set the

correctiononthebasisofmaterialproperties.Describedas:

None:Nocorrection.

Goodmanmethod:Generallysuitableforbrittlematerials.

Gerbermethod:Generallysuitableforductilematerials.

Soderbergmethod:Generallythemostconservative.

•Whenmeshingisdone,SolidWorkscreatestwotypeofshellelements:Top

faceshellelementsandBottomfaceshellelements.Thiselementscanbe

distinguishedbytheircolor.TheShellfaceareaofthedialogboxallows

you to select the faces that you want to use for performing fatigue

analysis.

• TheFatigue strength reduction factor (Kf) edit box is used to specify thevalue of fatigue reduction factor for allowing environment factor in

analysis.Usethisfactor,between0and1,toaccountfordifferencesin

test environment used to generate the S-N curve and the actual loading

environment. The program divides the alternating stress by this factor

beforereadingthecorrespondingnumberofcyclesfromtheS-Ncurve.This

is equivalent to reducing the number of cycles that cause failure at a

certainalternatingstress.Fatiguehandbookssuggestnumericvaluesfor

thefatiguestrengthreductionfactor.

• The Filter load cycles below edit box forces the system to filter out

load cycles with ranges smaller than the specified percentage of the

maximumrange.Forexample,ifyouspecify5%,theprogramignorescycles

withloadrangeslessthan5%ofthemaximumrangeoftheloadhistory.

Usethisparametertofilteroutnoisefrommeasuringdevices.

RUNNINGCONSTANTAMPLITUDEEVENTSONTHEMODEL

•StartanewstudyofFatiguebyusingtheConstantamplitudebuttonfromtheStudyPropertyManager;refertoFigure-15.ClickontheOKbuttontostarttheanalysis.

Figure-15.Constantamplitudebutton

•ClickontheAddEventbuttonfromtheFatiguedrop-downintheRibbon.The Add Event(Constant) PropertyManager will be displayed as shown in

Figure-16.

Figure-16.AddEventConstantPropertyManager

•Makesurethenumberofcyclesare1000intheCycleseditbox.ClickontheOKbuttonfromPropertyManager.

• Click on the Run This Study button from the Ribbon. The results of

constantloadingwillbedisplayedasshowninFigure-17.

Figure-17.Resultofconstantloadingfatigue

SELF-ASSESSMENT

Q1.Linearandnonlinearstructuralstudiesdonotpredictfailuredueto

fatigue.(T/F)

Q2. Results of static, nonlinear, or time history linear dynamic studies

canbeusedasthebasisfordefiningafatiguestudy.(T/F)

Q3. The number of cycles required for fatigue failure to occur at a

locationdependsonthematerialnotonthestressfluctuations.(T/F)

Q4.Cracksduetofatiguecandevelopanywhereinthematerialbutusually

occurontheboundaryfacesduetohigherstressfluctuations.(T/F)

Q5.Strengtheningthesurfacesofthemodeldoesnotaffectthelifeofthe

modelunderfatigueevents.(T/F)

Drop-Test

Chapter12

TopicsCovered


•Introduction

•StartingDrop-Test

•ApplyingMaterial

•Settingdropparameters



INTRODUCTIONInadroptestanalysis,thetimevaryingstressesanddeformationsdueto

an initial impact of the product with a rigid or flexible planar surface

(thefloor)arecalculated.Astheproductdeforms,secondaryinternaland

external impacts are also calculated, locating critical weaknesses or

failurepoints,aswellasstressesanddisplacements.Droptestanalysis

using SolidWorks Simulation enables you to visualize the elastic stress

wave propagating through the system so that the correct assembly methods

areused.

The maximum “g force” experienced by individual components is one of the

primary unknowns before a drop test. This is a critical parameter since

many electronic and mechanical components are not rated for further use

aboveaspecifiedmaximumgforce.UsingdroptestanalysiswithSolidWorks

Simulation, designers and engineers can measure the time varying

accelerations (g force) at any location within the product, providing

critical design information and reducing the number of physical tests

needed.Adesignteamcaneasilyverifyperformancewhiletheydesignand

select the correct materials, component shape, and fixture methods to

ensurethatcriticalcomponentsstaywithintheir“maxgforce”limits.

STARTINGDROPTEST•Openthepartonwhichyouwanttoperformthedrop-test.


•ClickontheDownarrowbelowtheStudyAdvisorbuttonandselecttheNewStudytoolfromthedrop-down.ListofanalysisstudieswillbedisplayedintheStudyPropertyManager.

•ClickontheDropTestbuttonfromthelistandclickontheOKbutton

from the PropertyManager. The tools related to drop-test will be


ApplyingMaterial•Right-clickonnameofthemodeli.e.ScaleBase.Ashortcutmenuwillbe

displayed.

•ClickonApply/EditMaterialbuttonfromtheshortcutmenu.TheMaterialdialogboxwillbedisplayed.

•SelecttheABSPCMaterialfromthePlasticcategoryintheleft;refertoFigure-2.

Figure-1.Toolsrelatedtodroptest

Figure-2.Materialdialogboxwithmaterialtobeselected

• Click on theApply button and then click on theOK button from the

dialogbox.

If you are working on an assembly then you can apply the contacts as

discussedinearlierchapters.

CreatingMesh•Right-clickontheMeshintheAnalysisManager.Ashortcutmenuwillbedisplayed.

•ClickontheSimplifyModelforMeshingbuttonfromtheshortcutmenu.TheSimplifytaskpanewillbedisplayed;refertoFigure-3.

Figure-3.Simplifytaskpane

•ClickontheFindNowbuttontofindtheareasthatcreatecomplexityinmeshing.ThecomplexareasaredisplayedbelowResultsintheSimplifytaskpane;refertoFigure-4.

Figure-4.Resultsintaskpane

•ClosetheSimplifytaskpaneandselectalltheelementsbyholdingCTRLkeywhileselectingfromtheFeatureManager.

• Right-click on any of the selected element and select the Suppressbutton;refertoFigure-5.

Figure-5.Suppressbutton

•Ondoingso,theselectedelementswillbesuppressed.

•Again,right-clickonMeshintheAnalysisManagerandselecttheCreateMesh button. The Mesh PropertyManager will be displayed; refer to

Figure-6.


• Set the mesh density as per your system capabilities and accuracy

requirement.

•ClickontheOKbuttonfromthePropertyManagertocreatethemesh.

ParametersforDrop

•Right-clickontheSetupnodefromtheAnalysisManager.Ashortcutmenuwillbedisplayed;refertoFigure-7.

• Click on the Define/Edit button from the menu. The Drop Test SetupPropertyManagerwillbedisplayed;refertoFigure-8.

Figure-7.Setupshortcutmenu

Figure-8.DropTestSetupPropertyManager

•Ifyouknowthevelocityoftheobjectbeingdroppedthenclickonthe

Velocity at impact radio button from the Specify rollout in the

PropertyManager.TheVelocityat Impactrolloutwillbedisplayedinthe


Figure-9.VelocityatImpactrollout

•SelectthereferenceforvelocitydirectionandselecttheReversebuttonadjacenttotheselectionboxintherollout.

•EnterthedesiredvelocityintheeditboxinVelocityatImpactrollout.

• If you know height of the object from where it is being dropped, then

click on the Drop height radio button. The Height rollout will be

displayed;refertoFigure-10.NotethattheDropheightradiobuttonisselectedbydefault.

Figure-10.Heightrollout

• Select the From centroid radio button if you want to specify the dropheight from centroid of the model or select the From lowest point radiobutton if you want to specify the height from the lowest point of the

model.

•SpecifythedropheightintheeditboxinHeightrollout.

• Click in the Pink selection box in theGravity rollout and select theplane/face/edgeforspecifyingthegravitydirectionreference.

•Selectthefacefordirectionreference;refertoFigure-11.

Figure-11.Faceselectedforgravityreference

•Youcanchangethegravitationalaccelerationasperyourrequirementby

usingtheGravityMagnitudeeditboxintheGravityrollout,ifrequired.

• Select theNormal to gravity radio button in theTarget rollout if thetargetplane(ground)isnormaltogravitydirection.

•SelecttheParalleltoref.planeradiobuttonandselectthereferenceplaneforspecifyingthegroundorientationasperyourrequirement.

•Youcanspecifythefrictioncoefficientforselectedmaterialbyusing

theFrictionCoefficienteditbox,ifrequired.

•IftheflooristoughthenselecttheRigidtargetradiobutton.IfyourfloorissoftthenselecttheFlexibletargetradiobuttonandspecifytherelatedparametersintheStiffnessandThicknessrolloutdisplayedinthePropertyManager.

•TheeditboxinContactDampingrolloutisusedtospecifythedampingratioforcollision.


PropertyManagertoapplythesettings.

RunningtheAnalysis•ClickontheRunbuttonfromtheRibbon.Systemwillstartsolvingtheanalysis.

• After the analysis is solved, the results will be displayed; refer to

Figure-12.

Figure-12.Results

• You can create more plots by right-clicking on Results node in the

AnalysisManagerandselectingthedesiredresultoption.

PressureVesselDesign&DesignStudy

Chapter13

TopicsCovered


•StartingPressureVesselDesign.

•InclusionofAnalyses

•SimulatingDesignStudy

•StartingDesignStudy

•SpecifyingVariables

•SettingConstraints

•SettingGoals

•Evaluatingresults

INTRODUCTIONPressure vessels are containers that store the pressurized fluids. A

pressure vessel can be of any practical shape but generally spherical,

cylindrical, and conical shapes are employed. The most important question

for pressure vessel designer is whether the designed vessel will sustain

therequired conditions or not. SolidWorks Simulation provides a separate

optiontoperformthisstudynamedPressureVesselDesignstudy.

InaPressureVesselDesignstudy,youcombinetheresultsofstaticstudieswith the desired factors. Each static study has a different set of loads

that produce corresponding results. These loads can be dead loads, live

loads(approximatedbystaticloads),thermalloads,seismicloads,andso

on. The Pressure Vessel Design study combines the results of the static

studiesalgebraicallyusingalinearcombinationorthesquarerootofthe

sumofthesquares(SRSS).

BeforewestartperformingthePressureVesselDesignstudy,theremustbe

two or more static analyses performed on the vessel earlier. In the next

example, we have already performed two static analyses and one thermal

analysisonthemodel.Detailsoftheseanalysesaregivenasfollows:

ThermalAnalysis1ParametersforthermalanalysisaregiveninFigure-1.

Figure-1.Parametersforthermalanalysis

You can perform the analysis as per the above figure for your practice.

Note that the analysis is already performed in the part file supplied in

theResourcekit.

StaticAnalysis1&2IntheFigure-2,theparametersforstaticanalysis1aregivenandinthe

Figure-3parametersforstaticanalysis2aregiven.

Figure-2.Parametersforstaticanalysis1

Figure-3.Parametersforstaticanalysis2

STARTINGPRESSUREVESSELDESIGNSTUDY•Openthefileonwhichyouhaveperformedtheabovegivenanalyses.

• Click on theSimulation tab in theRibbon and click on the down arrowbelowStudyAdvisor.Listoftoolswillbedisplayed.

•ClickontheNewStudybuttonandselectthePressureVesselDesignbuttonfromthePropertyManager.

•ClickontheOKbuttonfromthePropertyManagertodisplaythetoolsrelatedtoPressureVesselDesignStudy;refertoFigure-4.

Figure-4.Toolsforpressurevesseldesign

SetupforDesignStudy•RightclickontheSetupnodeintheAnalysisManager.Ashortcutmenuwillbedisplayed;refertoFigure-5.

• Click on the Define/edit button. The Result Combination SetupPropertyManagerwillbedisplayed;refertoFigure-6.

Figure-5.Shortcutmenuforsetup

Figure-6.ResultCombinationSetupPropertyManager

There are two ways to combine various analyses results to study pressure

vessel design; Linear combination and SRSS. Select theLinear combinationradio button to linearly add the results of various studies to display

finalresult.IfyouselecttheSRSSradiobuttonthenthesquarerootofthesumofthesquaresstudyresultswillbeusedtorepresentthefinal

result.

• Click in the field belowStudy column, the field will be converted todrop-down.

•Clickonthedownarrowofdrop-down.Thelistofstaticanalysesstudies

willdisplayed;refertoFigure-7.

Figure-7.Listofstudies

•SelecttheStatic1studyfromthelist.1factorwillautomaticallyappearintheFactorcolumnadjacenttothestudyandonemorerowwillbeaddedbelowtheselectedfield.

•ClickontheemptyfieldunderStudycolumnandselecttheStatic2study

fromthedrop-downasdiscussedearlier.


RunningtheDesignStudy• Click on theRun button in theRibbon. The combining process of twostudieswillstart.

•Afterthestudyiscomplete,theresultswillbedisplayedintheResultnodeoftheAnalysisManager;refertoFigure-8.

Figure-8.Resultsaftercombination

•Right-clickontheResultsnodeandselecttheDefineFactorofSafetyPlotbutton. TheFactor of Safety PropertyManager will be displayed; refer toFigure-9.

Figure-9.FactorofsafetyPropertyManager

•ClickontheOKbuttonfromthePropertyManager.Thefactorofsafetyplotwillbecreatedinthemodelingarea;refertoFigure-10.

Figure-10.Factorofsafetyplot

DESIGNSTUDYDesign Study is used to perform the optimization of the model. There are

variousparametersofanobjectthatdecidewhetherthemodelundertesting

willsustainorfailunderthegivencondition.Outofalltheparameters

ofamodel,thereareafewparametersofourconcernthatwewanttouse

forsatisfyingourobjective.InaDesignStudy,ourobjectivecanbe:

•Reducingthemassofthemodel.

•Decreasingthetotalmanufacturingcostofthemodel.

•Increasingthestrengthofthemodelandsoon.

To achieve these objective, we need to manipulate with dimensions,

materials,processandsoon.InSolidWorksSimulationDesignStudyisused

toperformanoptimizationorevaluatespecificscenariosofyourdesign.

You can plot the updated bodies and the calculated results for different

iterationsorscenariosbyselectingtheircolumnsontheResultsViewtab.

Youtackleavastnumberofproblemsusingadesignstudy.

Youcan:

• Define multiple variables using any simulation parameter, or driving

globalvariable.

•Definemultipleconstraintsusingsensors.

•Definemultiplegoalsusingsensors.

•Analyzemodelswithoutsimulationresults.Forexample,youcanminimize

themassofanassemblywiththevariables,densityandmodeldimensions,

andtheconstraint,volume.

•Evaluatedesignchoicesbydefiningaparameterthatsetsbodiestouse

differentmaterialsasavariable.

TheproceduretousetheDesignStudyisgivennext.

Before starting the design study, it is important to understand that the

designstudyisakindofmacrowhichperformsaspecifictypeofanalysis

with a varying values of a specific parameters. For example, we have

performedastaticanalysisonatubeunderaspecificpressureandwefind

thatitsfactorofsafetyis64.Then,wewillperformadesignstudyto

findoutthethicknessoftubewhichisoptimumi.e.factorofsafetyis

greater than 1 and thickness of tube is minimum possible. In the next

example,wehaveperformedsuchatestonthemodel.

StartingDesignStudy•Openthemodelonwhichyouhaveperformedtherelevantanalysis.Inthis

example,wehaveperformedastaticanalysisandwehavefoundtheresults

asgiveninFigure-11.

Figure-11.Factorofsafetyofexample

• From the above figure, you can find that the factor of safety of the

modelunderthegiventestis11.

•Ifwecheckthedimensionsthenthethicknessofthemodelis7mm;refertoFigure-12.

Figure-12.Thicknessoftube

• Now, click on the Simulation tab in theRibbon. The tools related toanalysiswilldisplay.

•ClickonthedownarrowbelowStudyAdvisorandselecttheNewStudytoolfrom the list of tools displayed. The Study PropertyManager will be

displayed.

• Click on theDesign Study button and click on theOK button from the

PropertyManager.

•TheDesignStudypanewillbedisplayed;refertoFigure-13.

Figure-13.Designstudypane

SettingoptionsforDesignStudy•ClickontheDesignStudyOptionsbuttonfromtheDesignStudypane;referto Figure-14. The Design Study Properties PropertyManager will be


Figure-14.DesignStudyOptionsbutton

Figure-15.DesignStudyPropertiesPropertyManager

•Selecttherequiredradiobuttonandsetthedesiredparameterslike;for

fastresults,clickontheFastresultsradiobutton.

Specifyingparametersthataretobechanged• Click on the down arrow under the Variables node. A list of variable

optionswillbedisplayed;refertoFigure-16.

Figure-16.Variablesdrop-down

• Click on the Add Parameter option from the drop-down list. The

Parameters dialog box will be displayed and you will be prompted to

selectadimensionthatistobevaried;refertoFigure-17.

Figure-17.Parametersdialogbox

•Clickonthedimensionofthemodelthatyouwanttomakevariable;refer

toFigure-18.TheselecteddimensionwillbeaddedundertheValuecolumnintheParametersdialogbox.

Figure-18.Dimensionselectedasvariable

•ClickinthefieldbelowNamecolumninthedialogboxandspecifythenameasThickness;refertoFigure-19.

Figure-19.Nameofparameter

•Ifyouwanttospecify,thenclickinthenamefieldofsecondrowand

followthesameprocedure.Youcanalsospecifyotherparametersinspite

ofdimensions.Todoso,clickonthedownarrownexttoModelDimensionin Category column and select the desired category. There are four

categories from which you can specify the variables:Model Dimension,GlobalVariable,Simulationdata,andMaterialdata.

•Afterspecifyingthevariables,clickontheOKbuttonfromthedialog

box. The variable will be added in theDesign Study pane and its rangewillbedisplayed;refertoFigure-20.

Figure-20.Designvariablewithrange

•Weknowthatthethicknessofourmodelis7mmwithFactorofSafetyas11. Now, we need to move below this thickness value to get the optimumthicknessofthetube.

•ChangethevalueofMin,Max,andStepasshowninFigure-21byusingthespinners.

Figure-21.Valuestobechanged

Specifyingrestrictionsforchanges• Click on the down arrow under theConstraints node in theDesign Studypane.Alistofoptionswillbedisplayed.

•ClickontheAddSensoroptionfromthelist.TheSensorPropertyManagerwillbedisplayed;refertoFigure-22.

Figure-22.SensorPropertyManager

•Clickonthedrop-downintheSensorTyperollout.Alistofoptionswillbedisplayed.

•SelecttheSimulationDataoptionfromthelist;refertoFigure-23.

Figure-23.SimulationDataoption

•Ondoingso,theoptionsrelatedtosimulationdatawillbedisplayedin

thePropertyManager.

•ClickontheResultsdrop-downintheDataQuantityrolloutandselecttheFactorofSafetyoption;refertoFigure-24.

Figure-24.Factorofsafetyoption

•ClickontheOKbuttonfromtheSensorPropertyManagertoaddtheFactorof Safety constraint. The constraint will be added in the Design Studypane;refertoFigure-25.

Figure-25.FactorofsafetyinDesignStudypane

•ClickonthedownarrownexttoislessthanfieldandselecttheIsgreaterthanoption;refertoFigure-26.

Figure-26.Optiontobeselected

SettingGoalforthestudy•ClickonthedownarrowundertheGoalsnode.Alistofoptionswillbedisplayed;refertoFigure-27.

Figure-27.Goalsdropdown

• Click on the Add Sensor option. The Sensor PropertyManager will be

displayedasdiscussedearlier;refertoFigure-28.

Figure-28.SensorPropertyManagerforgoals

•ClickontheOKbuttonfromthePropertyManagertosetthemasstobeminimized.TheMasswillbeaddedasgoalintheDesignStudypane;refertoFigure-29.

Figure-29.GoaladdedinDesignStudy

RunningtheStudyWehavespecifiedallthenecessaryparametersforthestudyandareready

fortheanalysis.

•ClickontheRunbuttonintheDesignStudypane,thedesignstudywillstart.

• After the study is solved, the results will be displayed as shown in

Figure-30.

Figure-30.Resultsofdesignstudy

• The green highlighted box displays the optimum result for the analysis

anditsrelatedparametersusedforoptimization.

Youcanspecifymorevariablesforchangingthedesignandtesttheresults

forpractice.

FundamentalsofFEA

Chapter14

TopicsCovered


•IntroductiontoFEA.

•GeneralDescriptionofFEA

•SolvingaproblemwithFEA

•FEAV/sClassicalMethods

•FEAV/sFiniteDifferentMethod

•NeedforStudyingFEM

•RefiningMesh

•HigherorderelementV/sRefinedMesh

•OptimumprocessofFEAthroughSolidWorksSimulation

INTRODUCTIONThe finite element analysis is a numerical technique. In this method all

thecomplexities of the problems, like varying shape, boundary conditions

and loads are maintained as they are but the solutions obtained are

approximate.Becauseofitsdiversityandflexibilityasananalysistool,

it is receiving much attention in engineering. The fast improvements in

computerhardwaretechnologyandslashingofcostofcomputershaveboosted

this method, since the computer is the basic need for the application of

thismethod.Anumberofpopularbrandoffiniteelementanalysispackages

arenowavailablecommercially.SomeofthepopularpackagesareSolidWorks

Simulation,NASTRAN,NISA,andANSYS.Usingthesepackagesonecananalyse

severalcomplexstructures.

The finite element analysis originated as a method of stress analysis in

the design of aircrafts. It started as an extension of matrix method of

structuralanalysis.Todaythismethodisusednotonlyfortheanalysisin

solid mechanics, but even in the analysis of fluid flow, heat

transfer,electricandmagneticfieldsandmanyothers.Civilengineersuse

this method extensively for the analysis of beams, space frames, plates,

shells, folded plates, foundations, rock mechanics problems and seepage

analysis of fluid through porous media. Both static and dynamic problems

canbehandledbyfiniteelementanalysis.Thismethodisusedextensively

for the analysis and design of ships, aircraft, space crafts, electric

motorsandheatengines.

GENERALDESCRIPTIONOFTHEMETHODInengineeringproblemstherearesomebasicunknowns.Iftheyarefound,

thebehavioroftheentirestructurecanbepredicted.Thebasicunknowns

or the Field variables which are encountered in the engineering problems

are displacements in solid mechanics, velocities in fluid mechanics,

electricandmagneticpotentialsinelectricalengineeringandtemperatures

inheatflowproblems.

Inacontinuum,theseunknownsareinfinite.Thefiniteelementprocedure

reduces such unknowns to a finite number by dividing the solution region

into small parts called elements and by expressing the unknown field

variables in terms of assumed approximating functions (Interpolating

functions/Shapefunctions)withineachelement.Theapproximatingfunctions

aredefinedintermsoffieldvariablesofspecifiedpointscallednodesor

nodal points. Thus in the finite element analysis, the unknowns are the

field variables of the nodal points. Once these are found the field

variablesatanypointcanbefoundbyusinginterpolationfunctions.

After selecting elements and nodal unknowns next step in finite element

analysisistoassembleelementpropertiesforeachelement.Forexample,

insolidmechanics,wehavetofindtheforce-displacementi.e.stiffness

characteristics of each individual element. Mathematically this

relationshipisoftheform

where[k]eiselementstiffnessmatrix,{δ}

eisnodaldisplacementvectorof

theelementand{F}eisnodalforcevector.Theelementofstiffnessmatrix

kij represent the force in coordinate direction ‘i’ due to a unit

displacement in coordinate direction ‘j’. Four methods are available for

formulating these element properties viz. direct approach, variational

approach, weighted residual approach and energy balance approach. Any one

of these methods can be used for assembling element properties. In solid

mechanics variational approach is commonly employed to assemble stiffness

matrixandnodalforcevector(consistentloads).

Element properties are used to assemble global properties/structure

properties to get system equations [k] {δ } = {F}. Then the boundary

conditions are imposed. The solution of these simultaneous equations give

the nodal unknowns. Using these nodal values additional calculations are

made to get the required values e.g. stresses, strains, moments, etc. in

solidmechanicsproblems.

Thusthevariousstepsinvolvedinthefiniteelementanalysisare:

(i)Selectsuitablefieldvariablesandtheelements.

(ii)Discritisethecontinua.

(iii)Selectinterpolationfunctions.

(iv)Findtheelementproperties.

(v)Assembleelementpropertiestogetglobalproperties.

(vi)Imposetheboundaryconditions.

(vii)Solvethesystemequationstogetthenodalunknowns.

(viii)Maketheadditionalcalculationstogettherequiredvalues.

ABRIEFEXPLANATIONOFFEAFORASTRESSANALYSISPROBLEM

Thestepsinvolvedinfiniteelementanalysisareclarifiedbytakingthe

stressanalysisofatensionstripwithfillets(referFigure-1).Inthis

problemstressconcentrationistobestudiesinthefilletzone.Sincethe

problemishavingsymmetryaboutbothxandyaxes,onlyonequarterofthe

tensionstripmaybeconsideredasshowninFigure-2.Aboutthesymmetric

axes, transverse displacements of all nodes are to be made zero. The

variousstepsinvolvedinthefiniteelementanalysisofthisproblemare

discussedbelow:

Step 1: Four noded isoparametric element is selected for the analysis

(However note that 8 noded isoparametric element is ideal for this

analysis). The four noded iso-parametric element can take quadrilateral

shapealsoasrequiredforelements12,15,18,etc.Asthereisnobending

ofstrip,onlydisplacementcontinuityistobeensuredbutnottheslope

continuity.Hencedisplacementsofnodesinxandydirectionsaretakenas

basicunknownsintheproblem.

Figure-1.TensionStripwithFillet

Figure-2.Descritizationofquateroftensionstrip

Step 2: The portion to be analysed is to be discretised. Figure-2 shows

discretised portion. For this 33 elements have been used. There are 48

nodes.Ateachnodeunknownsarexandycomponentsofdisplacements.Hence

inthisproblemtotalunknowns(displacements)tobedeterminedare48×2

=96.

Step3:Thedisplacementofanypointinsidetheelementisapproximatedby

suitablefunctionsintermsofthenodaldisplacementsoftheelement.For

thetypicalelement(Fig.1.3b),displacementsatPare

u=ΣNiui=N

1u1+N

2u2+N

3u3+N

4u4

andv=ΣNivi=N

1v1+N

2v2+N

3v3+N

4v4…(1.2)

TheapproximatingfunctionsNiarecalledshapefunctionsorinterpolation

functions.Usuallytheyarederivedusingpolynomials.

Step4:Nowthestiffnesscharactersandconsistentloadsaretobefound

foreachelement.Therearefournodesandateachnodedegreeoffreedom

is 2. Hence degree of freedom in each element is 4 × 2 = 8. The

relationship between the nodal displacements and nodal forces is called

elementstiffnesscharacteristics.Itisoftheform

[k]e{δ}

e={F}

e,asexplainedearlier.

Fortheelementunderconsideration,keis8×8matrixandδ

e and F

e are

vectors of 8 values. In solid mechanics element stiffness matrix is

assembledusingvariationalapproachi.e.byminimizingpotentialenergy.

Iftheloadisactinginthebodyofelementoronthesurfaceofelement,

itsequivalentatnodalpointsaretobefoundusingvariationalapproach,

sothatrighthandsideoftheaboveexpressionisassembled.Thisprocess

iscalledfindingconsistentloads.

Step5:Thestructureishaving48×2=96displacementandloadvector

componentstobedetermined.

Henceglobalstiffnessequationisoftheform

[k]{δ}={F}

96×9696×196×1

Each element stiffness matrix is to be placed in the global stiffness

matrix appropriately. This process is called assembling global stiffness

matrix.InthisproblemforcevectorFiszeroatallnodesexceptatnodes

45,46,47and48inxdirection.Forthegivenloadingnodalequivalent

forcesarefoundandtheforcevectorFisassembled.

Step6:Inthisproblem,duetosymmetrytransversedisplacementsalongAB

andBCarezero.Thesystemequation[k]{δ}={F}ismodifiedtoseethat

thesolutionfor{δ}comesoutwiththeabovevalues.Thismodificationof

systemequationiscalledimposingtheboundaryconditions.

Step7:Theabove96simultaneousequationsaresolvedusingthestandard

numerical procedures like Gausselimination or Choleski’s decomposition

techniquestogetthe96nodaldisplacements.

Step8:Nowtheinterestoftheanalystistostudythestressesatvarious

points. In solid mechanics the relationship between the displacements and

stressesarewellestablished.Thestressesatvariouspointsofinterest

maybefoundbyusingshapefunctionsandthenodaldisplacementsandthen

stressescalculated.Thestressconcentrationsmaybestudiesbycomparing

thevaluesobtainedatvariouspointsinthefilletzonewiththevaluesat

uniformzone,farawayfromthefillet(whichisequaltoP/b2t).

FINITEELEMENTMETHODV/SCLASSICALMETHODS

1.Inclassicalmethodsexactequationsareformedandexactsolutionsare

obtainedwhereasinfiniteelementanalysisexactequationsareformedbut

approximatesolutionsareobtained.

2. Solutions have been obtained for few standard cases by classical

methods, where as solutions can be obtained for all problems by finite

elementanalysis.

3. Whenever the following complexities are faced, classical method makes

thedrasticassumptions’andlooksforthesolutions:

(a)Shape

(b)Boundaryconditions

(c)Loading

Figure-3showssuchcasesintheanalysisofslabs(plates).

Togetthesolutionintheabovecases,rectangularshapes,sameboundary

conditionalongasideandregularequivalentloadsaretobeassumed.In

FEMnosuchassumptionsaremade.Theproblemistreatedasitis.

4. When material property is not isotropic, solutions for the problems

becomeverydifficultinclassicalmethod.Onlyfewsimplecaseshavebeen

tried successfully by researchers. FEM can handle structures with

anisotropicpropertiesalsowithoutanydifficulty.

5.Ifstructureconsistsofmorethanonematerial,itisdifficulttouse

classicalmethod,butfiniteelementcanbeusedwithoutanydifficulty.

6.Problemswithmaterialandgeometricnon-linearitiescannotbehandled

byclassicalmethods.

ThereisnodifficultyinFEM.

Figure-3.Analysisofslab

Hence FEM is superior to the classical methods only for the problems

involving a number of complexities which cannot be handled by classical

methodswithout making drastic assumptions. For all regular problems, the

solutionsbyclassicalmethodsarethebestsolutions.Infact,tocheckthe

validityoftheFEMprogramsdeveloped,theFEMsolutionsarecomparedwith

thesolutionsbyclassicalmethodsforstandardproblems.

FEMVSFINITEDIFFERENCEMETHOD(FDM)1. FDM makes pointwise approximation to the governing equations i.e. it

ensurescontinuityonlyatthenodepoints.Continuityalongthesidesof

grid lines are not ensured. FEM make piecewise approximation i.e. it

ensures the continuity at node points as well as along the sides of the

element.

2.FDMdonotgivethevaluesatanypointexceptatnodepoints.Itdonot

giveanyapproximatingfunctiontoevaluatethebasicvalues(deflections,

incaseofsolidmechanics)usingthenodalvalues.FEMcangivethevalues

atanypoint.Howeverthevaluesobtainedatpointsotherthannodesareby

usingsuitableinterpolationformulae.

3.FDMmakesstairtypeapproximationtoslopingandcurvedboundariesas

shown in Figure-4. FEM can consider the sloping boundaries exactly. If

curved elements are used, even the curved boundaries can be handled

exactly.

Figure-4.FDMapproximationofshape

4. FDM needs larger number of nodes to get good results while FEM needs

fewernodes.

5. With FDM fairly complicated problems can be handled where as FEM can

handleallcomplicatedproblems.

NEEDFORSTUDYINGFEMNow,anumberofusersfriendlypackagesareavailableinthemarket.Hence

onemayaskthequestion‘WhatistheneedtostudyFEA?’.

Theaboveargumentisnotsound.Thefiniteelementknowledgemakesagood

engineer better while just user without the knowledge of FEA may produce

more dangerous results. To use the FEA packages properly, the user must

knowthefollowingpointsclearly:

1.Whichelementsaretobeusedforsolvingtheprobleminhand.

2.Howtodiscritisetogetgoodresults.

3.Howtointroduceboundaryconditionsproperly.

4.Howtheelementpropertiesaredevelopedandwhataretheirlimitations.

5.Howthedisplaysaredevelopedinpreandpostprocessortounderstand

theirlimitations.

6. To understand the difficulties involved in the development of FEA

programs and hence the need for checking the commercially available

packageswiththeresultsofstandardcases.

UnlessuserhasthebackgroundofFEA,hemayproduceworstresultsandmay

gowithoverconfidence.HenceitisnecessarythattheusersofFEApackage

shouldhavesoundknowledgeofFEA.

WarningToFeaPackageUsersWhenhandcalculationsaremade,thedesigneralwaysgetsthefeelofthe

structureandgetroughideaabouttheexpectedresults.Thisaspectcannot

beignoredbyanydesigner,whateverbethereliabilityoftheprogram,a

complexproblemmaybesimplifiedwithdrasticassumptionsandFEAresults

obtained. Check whether expected trend of the result is obtained. Then

avoid drastic assumptions and get more refined results with FEA package.

User must remember that structural behaviour is not dictated by the

computerprograms.Hencethedesignershoulddevelopfeelofthestructure

andmakeuseoftheprogramstogetnumericalresultswhicharecloseto

structuralbehaviour.

One of the main concern for using FEA applications is selection of

elements, in other words discretization. The process of modeling a

structureusingsuitablenumber,shapeandsizeoftheelementsiscalled

discretization. The modeling should be good enough to get the results as

closetoactualbehaviorofthestructureaspossible.

Inastructurewecomeacrossthefollowingtypesofdiscontinuities:

(a)Geometric

(b)Load

(c)Boundaryconditions

(d)Material.

GeometricDiscontinuitiesWherever there is sudden change in shape and size of the structure there

shouldbeanodeorlineofnodes.Figure-5showssomeofsuchsituations.

Figure-5.GeometricDiscontinuityinthepart

DiscontinuityofLoadsConcentrated loads and sudden change in the intensity of uniformly

distributed loads are the sources of discontinuity of loads. A node or a

line of nodes should be there to model the structure. Some of these

situationsareshowninFigure-6.

Figure-6.FEMModelandslabwithdifferentUDL

DiscontinuityofBoundaryconditionsIf the boundary condition for a structure suddenly change we have to

discretize such that there is node or a line of nodes. This type of

situationsareshowninFigure-7.

Figure-7.Slabwithintermediatewallandcolumns

MaterialDiscontinuityNodeornodelinesshouldappearattheplaceswherematerialdiscontinuity

isseen;refertoFigure-8.

Figure-8.MaterialDiscontinuity

REFININGMESHTo get better results the finite element mesh should be refined in the

followingsituations:

(a)Toapproximatecurvedboundaryofthestructure

(b)Attheplacesofhighstressgradients.

SuchasituationisshowninFigure-9.

Figure-9.Refinedmeshnearcurvedboundary

UseOfSymmetryWhereverthereissymmetryintheproblem,itshouldbemadeuse.Bydoing

so,lotofmemoryrequirementisreducedorinotherwordswecanusemore

elements (refined mesh) for the same capacity of computer memory. When

symmetryistobeused,itistobenotedthatatrightanglestotheline

ofsymmetrydisplacementiszero.

HIGHERORDERELEMENTSV/SREFINEDMESH

Accuracy of calculation increases if higher order elements are used.

Accuracycanalsobeincreasedbyusingmorenumberofelements.Limitation

onuseofnumberofelementscomesfromthetotaldegreesoffreedomthe

computercanhandle.Thelimitationmaybeduetocostofcomputationtime

also.Hencetousehigherorderelementswehavetouselessnumberofsuch

elements. The question arises whether to use less number of higher order

elementsormorenumberoflowerorderelementsforthesametotaldegree

of freedom. There are some studies in this matter keeping degree of

accuracy per unit cost as the selection criteria. However the cost of

calculation is coming down so much that such studies are not relevant

today.Accuracyaloneshouldbeselectioncriteriawhichmaybecarriedout

initially on the simplified problem and based on it element may be

selectionfordetailedstudy.

OPTIMUMPROCESSOFFEATHROUGHSOLIDWORKSSIMULATION

With the knowledge of the basics discussed above we can summarize the

processofperforminganalysisasfollows:

1. Construct the part(s) in a solid modeler. It is surprisingly easy to

accidentally build flawed models with tiny lines, tiny surfaces or tiny

interiorvoids.Thepartwilllookfine,exceptwithextremezooms,butit

may fail to mesh. Most systems have checking routines that can find and

repairsuchproblemsbeforeyoumoveontoanFEAstudy.Sometimesyoumay

have to export a part, and then import it back with a new name because

imported parts are usually subjected to more time consuming checks than

“native”parts.Whenmultiplepartsformanassembly,alwaysmeshandstudy

the individual parts before studying the assembly. Try to plan ahead and

introduce split lines into the part to aid in mating assemblies and to

locateloadregionsandrestraint(orfixtureorsupport)regions.Today,

constructionofapartisprobablythemostreliablestageofanystudy.

2.Defeaturethesolidpartmodelformeshing.Thesolidpartmaycontain

features, like a raised logo, that are not necessary to manufacture the

part,orrequiredforanaccurateanalysisstudy.Theycanbeomittedfrom

the solid used in the analysis study. That is a relative easy operation

supportedbymostsolidmodelers(suchasthe“suppress”optioninSW)to

help make smaller and faster meshes. However, it has the potential for

introducingserious,ifnotfatal,errorsinafollowingengineeringstudy.

This is a reliable modeling process, but its application requires

engineering judgment. For example, removing small radius interior fillets

can greatly reduces the number of elements and simplifies the mesh

generation.But,thatcreatessharpreentrantcornersthatcanyieldfalse

infinitestresses.

Those false high stress regions may cause you to overlook other areas of

truehighstresslevels.Smallholesleadtomanysmallelements(andlong

run times). They also cause stress concentrations that raise the local

stresslevelsbyafactorofthreeormore.Thedecisiontodefeaturethem

dependsonwheretheyarelocatedinthepart.Iftheylieinahighstress

regionyoumustkeepthem.Butdefeaturingthemisallowedifyouknowthey

occurinalowstressregion.Suchdecisionsarecomplicatedbecausemost

partshavemultiplepossibleloadingconditionsandalowstressregionfor

oneloadcasemaybecomeahighstressregionforanotherloadcase.

3.Combinemultiplepartsintoanassembly.Again,thisiswellautomated

and reliable from the geometric point of view and assemblies “look” as

expected. However, geometric mating of part interfaces is very different

for defining their physical (displacement, or temprature) mating. The

physicalmatingchoicesareoftenunclearandtheengineermayhavetomake

a range of assumptions, study each, and determine the worst case result.

Havingtousephysicalcontactsmakesthelinearproblemrequireiterative

solutionsthattakealongtimetorunandmightfailtoconverge.

4. Select the element type. Some FEA systems have a huge number of

available element types (with underlying theoretical restrictions). The

SolidWorkssystemhasonlythefundamentaltypesofelements.Namely,truss

elements (bars), frame elements (beams), thin shells (or flat plates),

thickshells,andsolids.TheSWsimulationsystemselectstheelementtype

(beginningin2009)basedontheshapeofthepart.Theuserisallowedto

covert a non-solid element region to a solid element region, and visa

versa.Knowingwhichclassofelementwillgiveamoreaccurateorfaster

solution requires training in finite element theory. At times a second

elementtypestudyisusedtohelpvalidateastudybasedonadifferent

elementtype.

5.Meshthepart(s)orassembly,rememberingthatthemeshsolidmaynotbe

thesameasthepartsolid.AgeneralruleinanFEAisthatyourcomputer

never has enough speed or memory. Sooner or later you will find a study

thatyoucannotexecute.Oftenthatmeansyoumustutilizeacrudemesh(or

at least crude in some region) and/or invoke the use of symmetry or

antisymmetryconditions.Localsolutionerrorsinastudyareproportional

totheproductofthelocalelementsizeandthegradientofthesecondary

variables(i.e.,gradientofstressorheatflux).Therefore,youexercise

mesh control to place small elements where your engineering judgment

estimateshighstress(orflux)regions,aswellaslargeelementsinlow

stressregions.

The local solution error also depends on the relative sizes of adjacent

elements. You do not want skinny elements adjacent to big ones. Thus,

automatic mesh generators have options to gradually vary adjacent element

sizesfromsmallesttobiggest.

Thesolidmodelsenttothemeshgeneratorfrequentlyshouldhaveloador

restraint(fixture)regionsformedbysplitlines,evenifsuchsplitsare

not needed for manufacturing the parts. The mesh typically should have

refinementsatsourceorloadregionsandsupportregions.

Ameshmustlooklikethepart,butthatisnotsufficientforacorrect

study. A single layer of elements filling a part region is almost never

enough.Iftheregioniscurved,orsubjectedtobending,youwantatleast

three layers of quadratic elements, but five is a desirable lower limit.

Forlinearelementsyouatleastdoublethosenumbers.

Most engineers do not have access to the source code of their automatic

mesh generator. When the mesher fails you frequently do not know why it

failedorwhattodoaboutit.Oftenyouhavetore-trythemeshgeneration

with very large element sizes in hopes of getting some mesh results that

cangivehintsastowhyotherattemptsfailed.Themeshingofassemblies

often fails. Usually the mesher runs out of memory because one or more

partshadaverysmall,oftenunseen,featurethatcausesahugenumberof

tiny elements to be created. You should always attempt to mesh each

individualparttospotsuchproblemsbeforeyouattempttomeshthemasa

memberofanassembly.

Automatic meshing, with mesh controls, is usually simple and fast today.

However,itisonlyasreliableasthemodifiedpartorassemblysupplied

to it. Distorted elements usually do not develop in automatic mesh

generators, due to empirical rules for avoiding them. However, distorted

elements locations can usually be plotted. If they are in regions of low

gradientsyoucanusuallyacceptthem.

You should also note that studies involving natural frequencies are

influencedmostbythedistributionofthemassofthepart.Thus,theycan

still give accurate results with meshes that are much cruder than those

thatwouldbeacceptableforstressorthermalstudies.

6. Assign a linear material to each part. Modern FEA systems have a

materiallibrarycontainingthe“linear”mechanical,thermal,and/orfluid

properties of most standardized materials. They also allow the user to

define custom properties. The property values in such tables are often

misinterpretedtobemoreaccurateandreliablethantheyactuallyare.The

reportedpropertyvaluesareacceptedaveragevaluestakenfrommanytests.

Rarelyarethereanydataaboutthedistributionoftestresults,orwhat

standarddeviationwasassociatedwiththetests.Mosttestsyieldresults

thatfollowa“bellshaped”curvedistribution,orasimilarskewedcurve.

Whenyouacceptatabulatedpropertyvalueasasinglenumbertobeusedin

the FEA calculation remember it actually has a probability distribution

associatedwithit.Youneedtoassignacontributiontothetotalfactor

ofsafetytoallowforvariationsfromthetabulatedpropertyvalue.

Thevaluesofpropertiesfoundinamaterialtablecanappearmoreorless

accuratedependingontheunitsselected.Thatisanillusionoftencaused

byconvertingonesetofunitstoanother,butnottruncatingtheresultto

thesamenumberofsignificantfiguresavailableintheactualtestunits.

For example, the elastic modulus of one steel is tabulated from the

original test as 210 MPa, but when displayed in other units it shows as

30,457,924.92psi.Whichonedoyoubelievetobetheexperimentalaccurate

value;the3digitvalueorthe10digitone?Theansweraffectshowyou

shouldviewandreportstressresults.Theaxialstressinabarisequal

totheelasticmodulustimesthestrain, .Thus,ifEis

only known to three or four significant figures then the reported stress

resultshouldhavenomoresignificantfigures.Materialdataareusually

morereliablethantheloadingvalues(considered

next),butlessaccuratethatthemodelormeshgeometries.

7.Selectregionsofthepart(s)tobeloadedandassignloadlevelsand

load types to each region. In mathematical terminology, load or flux

conditionsonaboundaryregionarecalledNeumannboundaryconditions,or

nonessential conditions. The geometric regions can be points (in theory),

lines,surfaces,orvolumes.Iftheyarenotexistingfeaturesofthepart,

then you should apply split lines to the part to create them before

activatingthemeshgenerator.Pointforces,orheatsources,arecommonin

undergraduatestudies,butinanFEAtheycausefalseinfinitestresses,or

heatflux.Ifyouincludethemdonotbemisleadbythehighlocalvalues.

Refining the mesh does not help since the smallest element still reports

nearinfinitevalues.

Inreality,pointloadsarebettermodeledasatotalforce,orpressure,

acting over a small area formed by prior split lines. Saint Venant’s

Principle states that two different, but statically equivalent, force

systemsactingonasmallportionofthesurfaceofabodyproducethesame

stress distributions at distance large in comparison with the linear

dimensions of the portion where the forces act. That also implies that

concentratedsourcesquicklybecomere-distributed.

Inundergraduatestaticsanddynamicscoursesengineersaretaughttothink

in terms of point forces and couples. Solid elements do not accept pure

couples as loads, but statically equivalent pressures can be applied to

solids and yield the correct stresses. Indeed, a couple at a point is

almostimpossibletocreate,sothedistributionofpressuresisprobably

morelikethetruesituation.

The magnitudes of applied loads are often guesses, or specified by a

governing design standard. For example, consider a wind load. A building

standardmayquoteapressuretobeappliedforagivenwindspeed.But,

howwelldoyouknowthewindspeedthatmightactuallybeexertedonthe

structure? Again, there probably is some type of “bell curve” around the

expected average speed. You need to assign a contribution to the total

factor of safety to allow for variations in the uncertainty of the load

valueoractualspatialdistributionofappliedloads.

Loading data are usually less accurate than the material data, but much

moreaccuratethattherestraintorsupportingconditionsconsiderednext.

8. Determine (or more likely assume) how the model interacts with the

surroundingsnotincludedinyourmodel.Thesearetherestraint(support,

or fixture) regions. In mathematical terminology, these are called the

essentialboundaryconditions,orDirichletboundaryconditions.Youcannot

afford to model everything interacting with a part. For many decades

engineers have developed simplified concepts to approximate surroundings

adjacent to a model to simplify hand calculations. They include roller

supports,smoothpins,cantilevered(encastre,orfixed)supports,straight

cable attachments, etc. Those concepts are often carried over to FEA

approachesandcanoversimplifythetruesupportnatureandleadtovery

largeerrorsintheresults.

Thechoiceofrestraints(fixations,supports)foramodelissurprisingly

difficult and is often the least reliable decision made by the engineer.

Smallchangesinthesupportscancauselargechangesintheresults.Itis

wise to try to investigate a number of likely or possible support

conditionsindifferentstudies.Whenindoubt,trytoincludemoreofthe

surroundingsupportmaterialandapplyassumedsupportconditionstothose

portionsatagreaterdistancefromcriticalpartfeatures.

Youneedtoassignacontributiontothetotalfactorofsafetytoallow

for variations in the uncertainty of how or where the actual support

conditionsoccur.Thatisespeciallytrueforbucklingstudies.

9. Solve the linear system of equations, or the eigenvalue problem. With

today’s numerical algorithms the solution of the algebraic system or

eigensystem is usually quite reliable. It is possible to cause ill-

conditionedsystems(largeconditionnumber)withmesheshavingbadaspect

ratios,orlargeelementsadjacenttosmallones,butthatisunlikelyto

happenwithautomaticmeshgenerators.

10.Checktheresults.Arethereactionsatthesupportsequalandopposite

to the sources you thought that you applied? Are the results consistent

withtheassumedlinearbehavior?Theengineeringdefinitionofaproblem

withlargedisplacementsisonewherethemaximumdisplacementismorethan

halfthesmallestgeometricthicknessofthepart.Theinternaldefinition

is a displacement field that significantly changes the volume of an

element.

That implies the element geometric shape noticeably changed from the

startingshape,andthattheshapeneedstobeupdatedinaseriesofmuch

smaller shape changes. Are the displacements big enough to require

resolutionwithlargedisplacementiterationsturnedon?Haveyouvalidated

the results with an analytic approximation, or different type of finite

element?Engineeringjudgmentsarerequired.

11. Post-process the solution for secondary variables. For structural

studies you generally wish to document the deflections, reactions and

stresses. For thermal studies you display the temperatures, heat flux

vectorsandreactionheatflows.Withnaturalfrequencymodelsyoushow(or

animate) a few mode shapes. In graphical displays, you can control the

numberofcontoursemployed,aswellastheirmaximumandminimumranges.

The latter is important if you want to compare two designs on a single

page. Limit the number of digits shown on the contour scale to be

consistentwiththematerialmodulus(orconductivity,etc.).Colorcontour

plotsoftendonotreproducewell,butgraphsdo,solearntousethemin

youdocumentation.

12. Determine (or more likely assume) what failure criterion applies to

yourstudy.Thisstageinvolvesassumptionsabouthowastructuralmaterial

mightfail.Thereareanumberoftheories.Mostarebasedonstressvalues

or distortional energy levels, but a few depend on strain values. If you

know that one has been accepted for your selected material then use that

one (as a contribution to the overall factor of safety). Otherwise, you

shouldevaluatemorethanonetheoryandseewhichistheworstcase.Also

keepinmindthatloadingorsupportuncertaintiescanleadtoarangeof

stress levels, and variations in material properties affect the strength

andunexpectedfailurescanoccurifthosetypesofdistributionshappento

intersectasinthenextfigure.

14. Optionally, post-process the secondary variables to measure the

theoreticalerrorinthestudy,andadaptivelycorrectthesolution.This

convergestoanaccuratesolutiontotheprobleminput,butperhapsnotto

theproblemtobesolved.Accurategarbageisstillgarbage.

15.Document,report,andfilethestudy.Thepartshape,mesh,andresults

shouldbereportedinimageform.Assumptionsonwhichthestudywasbased

shouldbeclearlystated,andhopefullyconfirmed.Thedocumentationshould

containan independent validation calculation, or two, from an analytical

approximationoranFEAbasedonatotallydifferentelementtype.

ProjectonAnalysis

Chapter15

TopicsCovered


•Project

•StaticAnalysis

•FrequencyAnalysis

•FatigueTest

PROJECT

In this project,we have a real-time problem of forging die. For your

understanding, I want to tell you that there are many components like

gears, shafts, rings, engine covers that are made with the help of a

forging machine. In a forging machine, a workpiece pre-heated at

temperatureofplasticdeformationisplacedinthebottomdieandtopdie

strikes to the workpiece. After this impact of 50kN to 1600kN on the

workpiece,theworkpiecetakestheshapeoftopandbottomdies;referto

Figure-1.

Figure-1.ForgingProcess

Now,wehavethebottomdiethatneedtobeanalyzedat115°Cofsurfacetemperatureandforceexertedonitssurfaceis200kN;refertoFigure-2andFigure-3.WeneedtofindouttheFactorofsafetyofthemodel.Ifit

is higher then methods to reduce the cost of model. If the FoS is lower

thenthemethodstoincreaseitforincreasingstrengthofthemodel.Also,

we need to check the model for Fatigue under the cycle of 100,000

loading/unloading. After performing the analysis, we will create a more

refinedmeshandthenwewillchecktheresultsagain.

Figure-2.Facesunderspecifiedtemperature

Figure-3.Facesundertheload

STARTINGSIMULATION•OpenthefileofdiemodelinSolidWorks(Thefileisavailableinthe

Resourcekit).

•ClickontheSimulationbuttonfromtheSOLIDWORKSAdd-InstabintheRibbon.TheSimulationtabwillbeaddedintheRibbon.

• Click on the Simulation tab. The tools related to simulation will be

displayed.

PERFORMINGTHESTATICANALYSIS• Click on the down arrow below Study Advisor in the Simulation tab’s

Ribbon.

•SelecttheNewStudybuttonfromthelistoftoolsdisplayed.TheStudyPropertyManagerwillbedisplayed.

•ClickontheStaticbuttonfromthePropertyManagerandclickontheOKbuttonfromthePropertyManager.

•ClickontheApplyMaterialbuttonfromtheRibbon.TheMaterial dialogboxwillbedisplayedasshowninFigure-4.


•Bydefault,theAlloySteelmaterialisselectedfromthelistintheleftofthedialogbox.Ifnotselectedthenselectit.

•ClickontheApplybuttonandthentheClosebuttonfromthedialogbox.

•ClickonthedownarrowbelowFixtureAdvisor button in theRibbon andselecttheFixedGeometrybuttonfromthelist.

•TheFixturePropertyManagerwillbedisplayed.•Selectthebottomfaceofthemodeltofixit;refertoFigure-5.

Figure-5.Facetobefixed


• Click on the down arrow below External Loads Advisor button in the

Ribbon.Thelistoftoolswillbedisplayed.

• Click on the Temperature button from the list. The TemperaturePropertyManagerwillbedisplayed.

•ClickontheSelectallexposedfacesbuttonfromthePropertyManager.Allthefaceswillgetselected.

•PressandholdtheCTRLkeyandselectthebottom,sideandtopfaceofthedie;refertoFigure-6.Thefaceswillgetdeselected.

Figure-6.Facesselectedfortemperature

•ClickontheTemperaturedrop-downintheTemperaturerolloutandselecttheCelsius(°C)option.

•ClickintheTemperatureeditboxandspecifythevalueas115.


•Again,clickonthedownarrowbelowExternalLoadsAdvisorbuttonintheRibbon.

•Select theForce button from the list of tools. TheForce PropertyManager will bedisplayed.

•Selectthefacesvisiblefromthetopofthemodel;refertoFigure-7.

Figure-7.Facesforapplyingforce

•ClickintheForceValueeditboxandspecifythevalueas200000N.

•SelecttheTotalradiobuttonfromthePropertyManagerandclickontheOKbutton.

•ClickontheRunbuttonfromtheRibbon.Aftertheanalysisissolvedtheresultwillbedisplayed;refertoFigure-8.

Figure-8.Resultofstaticanalysis

•Right-clickontheResultsnodeinAnalysisManagerandselecttheDefineFactorOfSafetyPlotoptionfromtheshortcutmenudisplayed.

•TheFactorofSafetyPropertyManagerwillbedisplayed;refertoFigure-9.

Figure-9.FactorofSafetyPropertyManager

• Click on theOK button from thePropertyManager. TheFactor of Safetyplotwillbedisplayed;refertoFigure-10.

Figure-10.FactorofSafetyplot

PERFORMINGTHEFREQUENCYANALYSIS• Click on the down arrow below Study Advisor and select theNew Studybuttonfromthelistdisplayed.

•ClickontheFrequencybuttonfromtheStudyPropertyManagerandclickon the OK button from the PropertyManager. The tools related to

frequencyanalysiswillbedisplayed.

•ClickontheApplyMaterialbuttonfromtheRibbon.TheMaterialdialogboxwilldisplay.

•SelecttheAlloySteelfromtheleftofthedialogbox.

•ClickontheApplybuttonandthenontheClosebuttonfromthedialogbox.

•Fixthebottomfaceofthedieasdoneinthepreviousanalysisbyusing

theFixedGeometrybutton.

•ClickontheRunbuttonfromtheRibbontoperformtheanalysis.•Aftertheanalysisiscomplete,thenaturalfrequenciesofthemodelwill

bedisplayed;refertoFigure-11.

Figure-11.Resultoffrequencyanalysis

• Make sure that the frequency of the machine vibration is not matching

withthenaturalfrequenciesofthemodel.

PERFORMINGFATIGUESTUDY•ClickonthedownarrowbelowStudyAdvisorintheRibbon.Listofthetoolswillbedisplayed.

• Click on the New Study tool. The Study PropertyManager will be

displayed.

• Click on theFatigue button from thePropertyManager and click on theOKbuttonfromthePropertyManager.ThetoolsrelatedtoFatigueanalysiswillbedisplayed.

•Right-clickonLoading(-ConstantAmplitude-)intheAnalysisManagerandselecttheAddEventoption;refertoFigure-12.TheAddEvent(Constant)PropertyManagerwillbedisplayed;refertoFigure-13.

Figure-12.AddEventoption

Figure-13.AddEventPropertyManager

•ClickintheCycleseditboxandspecifythevalueas100,000.

• Click on the Loading Type drop-down and select the Zero Based (LR=0)optionfromthedrop-downlist.

•ClickontheOKbuttonfromthePropertyManagertoaddtheevent.NotethatnameofpartwillbeaddedasanewnodeintheAnalysisManager.

•Right-clickonthenameofthepartandselecttheApply/EditFatigueDataoption;refertoFigure-14.TheMaterialdialogboxwillbedisplayedwiththeFatigueSNCurvestabactivated;refertoFigure-15.

Figure-14.Applyingfatiguedata

Figure-15.Materialdialogboxwithfatigueoptions

• Click on theDerive from material Elastic Modulus radio button and thenclick on the Based in ASME Carbon Steel curves radio button. (Due to

selectionoftheseradiobuttons,theSNcurveofacarbonsteelwillbe

usedwhichisderivedfromitselasticitycurve.)

• Click on theApply button and then click on theClose button from thedialogbox.Now,wearereadytoperformtheanalysis.

•ClickontheRunbuttonfromtheRibbon.Theanalyzingwillstart.•TheresultsoftheanalysiswillbeaddedintheResultsnode.

• Expand the node and double-click on the results to display the plot;

refertoFigure-16.

Figure-16.Fatigueresult

•Right-clickontheResultsnodeandselecttheDefineFatiguePlotoption;refer to Figure-17. The Fatigue Plot PropertyManager will be displayed;refertoFigure-18.

Figure-17.Definefatigueplotoption

Figure-18.FatiguePlotPropertyManager

•ClickontheLoadFactorradiobuttonandclickontheOKbuttonfromthe

PropertyManager. The load factor plot (in other words,Factor of Safetyforfatigue)willbedisplayed;refertoFigure-19.

Figure-19.Factorofsafetyfatigue

•Fromthescale,theyoucanfindthattheminimumfactorofsafetyofthe

fatiguestudyis3.6.

SinceourFactorofSafetyfortheproblemisoptimum,sowedonotrequiredtoperformtheDesignStudyasperformedinpreviouschapters.Although,youcanperformtheDesignStudytofindabetterproduct.

Now,Ihavealittleworkforyou:

GobacktoStaticStudyanalysisbyclickingontheStatic1tabatthebottombar of the modeling area. Note that the Factor of Safety is 2.1 for thisanalysis.Now,Right-clickontheMeshnodeintheAnalysisManager;refertoFigure-20.

Figure-20.ShortcutmenuforMesh

SelecttheCreateMeshbutton,makethemeshingextremelyfineandthenre-runthestaticanalysis.Now,checktheFactorofSafetyofthemodel.Isitthesameordifferent.

Ifdifferentthenwhy?Askyourtutor.

For online training on SolidWorks, SolidWorks Simulation and SolidWorks

Electrical, please write us at [email protected] or

[email protected]

TherearemanypointswhereyouwillneedthemodelingtoolsofSolidWorks

likewhencreatingsurfacesforsimplification.SolidWorks2017BlackBookfromthesameauthorcanbenefitinmodelingtools.Ifyouwanttolearn

theSolidWorksmodelingtoolsthenpleasehavelookonthebook.

PracticeQuestions

TopicsCovered


•Project

•StaticAnalysis

•FrequencyAnalysis

•FatigueTest

PROBLEM1

Sometimesweseepeoplefightingandinsomeextremecases,fightingwith

thehelpofBaseballbats.Wearenotheretodiscussconceptsoffighting

butoncethefightingisover,everybodyisbusytoseeeffectofbaseball

batonhumans.Duetounknownelasticpropertyofhumanbody,wecannot

performanalysistofindeffectofbaseballbatonhumans,butherewecan

checktheeffectofforceexertedonthebaseballbatduetosomefreaks;

refertoFigure-1.

Figure-1.Problem1

Weassumeittobeastaticanalysis.Checkwhetherthebatwillbreakor

not.

PROBLEM2

Thewallofahouseis7mwide,6mhighand0.3mthickmadeupofbrick.

The thermal conductivity of brick is k = 0.6 W/m.K. If the inside

temperatureofwallis16 oCandoutsidetemperatureis6 oCthenfindout

theheatlostfrominsidewalltooutsidewallinasteadystatecondition.

ThemodelisgiveninFigure-2.

Figure-2.Problem2

Note that to perform this thermal analysis, you need to create a new

materialwiththermalpropertiesasfollow:

ThermalConductivity=0.6W/(m.K)

Specificheat=1214J/(kg.K)

Massdensity=2405kg/m3

PROBLEM3

Anaxialpullof35kNisappliedattheendsofashaftasshowninFigure-3. If the material is Alloy Steel then find the total elongation in theshaft.

Figure-3.Problem3shaft

PROBLEM4

Acastironlinkisrequiredtotransmitasteadytensileloadof45kN.The

initialboundaryconditionsaregiveninFigure-4.

Figure-4.Problemoflink

Findouttheoptimumthicknessoflinksothatfactorofsafetyis3.

PROBLEM5

A part of car jack assembly is displayed in Figure-5 with its boundary

conditions.Optimizetheassemblywithrespecttomaterialcost.Notethat

allthecontactsarenopenetrationasyoufindinarealcarjack.

Figure-5.Problem5

PROBLEM6

AnassemblyofcoolingfinsandCPUisdisplayedinFigure-6withboundary

conditions.Thebulktemperatureis300Kandoperatingtemperaturebandfor

CPUis304Kto354K.Checkiffinsareenoughtodissipatetheheat.If

notthenperformmodificationsinfintodissipateheat.Notethatfinsand

heatsinkareperfectlybondedforheattransfer.

Figure-6.Problem6

Documents

SolidWorks Simulation 2017 Black Book