Upload
saad-al-hely
View
196
Download
8
Tags:
Embed Size (px)
Citation preview
Design Optimization and Robust Design for Fatigue
Jeff Mentley HBM nCode Sumeet Parashar Esteco
Agenda
HBM nCode Intro Esteco Intro nCode DesignLife Overview modeFRONTIER Overview Robust Design Example Multi-Objective Design Optimization of a Connecting Rod Questions
From Physical Measurement to Virtual Testing
Projects Sensors
Services DAQ Hardware
Calibration DAQ Software Analysis & Data Processing
Simulation and Prediction
nCode DesignLife Overview
HBM-nCode Analysis and Simulation
nCode Product RangeData Processing System for Engineers Streamlining the Virtual Fatigue Engineering Process Web-based Processing for Engineering Data
Complex analysis to report, simply done Graphical, interactive & powerful analysis World leading fatigue analysis capabilities
Powerful fatigue analysis technology Integrated reporting and process encapsulation Fast, expandable, and scalable
Search, query and reporting data through secure web access. Analyze, trend and understand using configurable processing.
nCode DesignLifeTM Streamlining the Virtual Fatigue Engineering Process Intuitive and easy to use software for performing fatigue analysis of finite element models Efficiently analyze large finite element models and complete usage schedules. Wide range of fatigue analysis capabilities including stress-life, strain-life, multi-axial, weld analysis, virtual shaker table, and more. Highly configurable for the expert user. Plus Python enables new or proprietary fatigue methods to be added. Single environment for both Test and CAE data. Enables automation of complete analysis processes and reporting.
nCode DesignLifeTM - Capabilities Stress-Life (single, multi-curve, Haigh diagrams) Strain-Life (automated multi-axial corrections) Multi-axial safety factor (Dang Van) Seam welds and spot welds High temperature fatigue Vibration fatigue (shaker simulation) Multiple runs in a single analysis Complete duty cycles / flight spectrums Multi-threaded enabled for fast results Finite Element results supported4
Static (linear superposition) 4 Transient 4 Modal 4 Frequency Response 4 Linear & Non-linear
Major FE codes supported4
ANSYS 4 ABAQUS 4 NASTRAN 4 LS-Dyna
nCode DesignLifeTM User Interface
Running DesignLife in Batch
Flowproc (1) runs DesignLife process in batch Inputs4 DesignLife
flow 4 Flowproc script Specifies input data ( replaces drag and drop ) Modify glyph properties ( change property values saved in flow ) Only exposed properties of CAE Analysis glyphs
Outputs4 Files
with overwrite set to Yes
(1) Flowproc is not available under Hyperworks Licensing
nCode DesignLifeTM Summary
Predict Up-front durability assessment
Process Capture knowledge and integrate CAE & test
Productivity DesignLife can handle fatigue analysis with relative ease, and thisis down to the companys long standing expertise in this area. MCAD Magazine
Spend more time where it counts
modeFRONTIER Overview
Robust Design Example
Robust Design Example
Analysis tools: ANSYS WB for stress analyses nCode DesignLife for fatigue analysis Loading Fatigue Strength Surface Roughness
Robust Design
ANSYS Workbench Housing Model
Model Description Aluminum Pressure Loading Constrained at Mating surface Mounting screws
DesignLife Process
Statistical Fatigue Analysis
Material Properties Surface Finish Surface Treatment PASS FAIL Temperature Loads Notches Internal Stresses
stress
strength
Confidence of Survivalt = f (2Nf ) b 10 zse + f (2Nf ) c 10 zsp E
z : number of standard deviations from the mean se & sp : standard error of log(e) & log(p) respectively
Total strain amplitude
nominal life line :90% life line :
t =t =
f (2Nf ) b + f (2Nf ) c E
i.e. z = 0
50% 90%
f (2Nf ) b 10 1.28se + f (2Nf ) c 10 1.28sp E i.e. z = 1.28
Number of SDs from mean -3 -2 -1 090% 50%
% Certainty of survival 99.9 nominal life-line 97.7 90% confidence life-line 84 50
Reversals to failure
DesignLife Process
StrainLife Analysis Exposed properties load scale factor certainty of survival surface roughness Constant load provider 0 to 5 MPa 2nd Pass worst node Output CSV file
Running DesignLife using Flowproc
DOS Command to run flowproc: C:\nCode\GlyphWorks51\bin\flowproc /flow=cover_doe_notrans.flo /script=flowproc.script /verbose=yes cover_doe_notrans.flo flowproc.script DesignLife process file script file
Example script file
modeFRONTIER Workflow
modeFRONTIER Workflow
modeFRONTIER Workflow
modeFRONTIER Workflow
modeFRONTIER Workflow
modeFRONTIER Workflow
Robust Design Sensitivity Analysis
Student Chart for Sensitivity Analysis
Robust Design Life Distribution
Multi-Objective Design Optimization of a Connecting Rod
Multi-Objective Design Optimization of a Connecting Rod
Analysis tools: ANSYS WB for stress analyses of two working conditions: firing and return nCode DesignLife for fatigue analysis Minimize mass Minimize maximum stress Maximize fatigue life Maximum stress < 100 MP Fatigue life > 1e9
Objectives:
Constraints:
Design Variables
Design variables:1. Thickness scale (of center portion) (0.1~1.0) 2. Thickness (5 ~30 mm) 3. Upper fillet (1~100 mm) 4. Lower fillet (1~150 mm) 5. Upper width (3~10 mm) 6. Lower width (3~10 mm)
ANSYS Workbench Model
Firing Loadcase Return Loadcase 25 kN compressive 2500 N tensile load load Bearing supports Journal Pin
DesignLife Flow
Stress Life TimeStep load provider Firing Return 2nd Pass worst node Output CSV file
modeFRONTIER Workflow
NSGA-II more suitable for - Multiple objectives - Robust & global convergence - Better constraints handling - Discrete & continuous variables
modeFRONTIER Workflow
Sensitivity Analysis - Student Chart
Correlation analysis - Scatter Matrix
Feasible vs. Unfeasible
Pareto Froniter
Pareto Froniter
modeFRONTIER Workflow (3 Objectives)
Sensitivity analysis - Overall Student Chart
Tradeoff analysis - Bubble Chart
Tradeoff analysis - Parallel Coordinates
Each design represented as connected poly-line
Tradeoff analysis - Parallel Coordinates
Filter only Pareto designs
Tradeoff analysis - Parallel Coordinates
Filter based on designers preference
Summary
DesignLife allows virtual fatigue life predictions from FE results Batch operation of DesignLife allows its use by 3rd party optimization programs such as modeFRONTIER Combining DesignLIfe with modeFRONTIER allows4 Robust
Design 4 Shape optimization based on fatigue results
Jeffrey Mentley
Questions?
HBM - nCode 26555 Evergreen Road, Ste. 700 Southfield, MI 48076
(248) 945-4368 phone (248) 225-6844 cell [email protected] www.hbm.com/ncode