Improving Your Structural Mechanics Simulations … Your Structural Mechanics Simulations with ... ANSYS Workbench is ... Bolt pretension does not

© 2011 ANSYS, Inc. October 12, 20111

Improving Your Structural Mechanics Simulations with Release 14.0


What will Release 14.0 bring you?


MAPDL/WB Integration

Finite Element Information Access within ANSYS Mechanical


ANSYS Workbench is originally a geometry based tool. Many users however also need to control and access the finite element information.

Motivation


Spot Welds

Connections created internally at the solution level are available and can help understand the results

Reviewing Connections

Weak springs and MPC contacts as generated by the solver


Nodes can be grouped into named selectionsbased on selection logic, using locations or other characteristics – or manual selections

Selections of Nodes

Box Selection Node Picking Lasso Selection


Applying Loads and Orientations to Nodes

“Nodal orientation” allows users to orient nodes in an arbitrary coordinate system.

Direct FE loads and boundary conditions can be applied to selections of nodes.

Nodes are oriented in cylindrical system for loads and boundary condition definitions


Results on Node Selections

Results are displayed on elements for which all nodes are selected.

Nodes named selections allow to scope on specific regions of the mesh or remove undesired areas.

Results with first layer of quads removed

Results on quads layers only


Restart and Direct FE Loads

Nodal Forces and Pressures objects can be added to a restart analysis without causing the restart points to become invalid.

Other loads can now be modified without losing the restart points.

Analysis Settings tabular data: No restart point is lost

Added after initial solve

Second Load step modified for restart


MAPDL/WB Integration

Linear Dynamics in ANSYS Mechanical


Workbench and Mechanical enhancements

→MSUP Transient Analysis supported

→Joint feature can now be used in Harmonics, Random vibration analysis

→Reaction Force & Moment results is now supported

Modal Superposition Transient

Joints in HarmonicAnalyses

Reaction Forces in a Harmonic Analyses


Physics Coupling

Data Mapping


Motivation

Exchange files are frequently used to transfer quantities from one simulation to another.

Efficient mapping of point cloud data is required to account for misalignment, non matching units or scaling issues.


Supported Data Types

New at R14.0


Increased Accuracy

The smoothness of the mapped data depends on the density of the point cloud.

Several weighting options are available to accommodate various data quality.

Triangulation versus Kriging


Validating the Mapped Data

Visual tools have been implemented to control how well the data has been mapped onto the target structure


Importing Multiple Files

Multiple files can be imported for transient analyses or to handle different data to be mapped on multiple bodies


Rotating Machines

Studying Rotordynamics in ANSYS Mechanical


Motivation

ANSYS Mechanical users need to be able to quickly create shaft geometriesas well as analyze dynamic characteristics of rotating systems

Industrial fan (Venti Oelde)


Geometry Creation

Geometries can be imported from a CAD system or imported from a simple text file definition as used in preliminary design


Import/Export of Bearing Characteristics

ANSYS provides an interface that allows to import bearing characteristics from an external file


Specific Solver Settings

Rotordynamicsanalyses require a number of advanced controls:

→Damping

→Solver choice

→Coriolis effect


Campbell Diagrams

Campbell diagrams are used to identify critical speeds of a rotating shaft for a given range of shaft velocities


Composites

Enhanced Analysis Workflow and Advanced Failure Models for Composites


Motivation

Efficient workflows and in‐depth analysis tools are required to model and understand complex composites structures


Defining Material Properties

Composites material require specific definitions including orthotropic properties, as well as some constants for failure criteria (Tsai‐Wu, Puck, LaRc03/04, Hashin)


Manually Defining Layers on Simple Geometries

Users can define simple layered sections for a shell body as well as define thicknesses and angles as parameters


Defining Layers on Complex Geometries

For complex geometries, the ANSYS Composite PrepPosttool is used and layer definitions are imported in the assembly model in ANSYS Mechanical.

Courtesy of TU Chemnitz and GHOST Bikes GmbH


Investigating Composites Results

ANSYS Mechanicalsupports layerwisedisplay of results.

ANSYS Composite PrepPost offers comprehensive capabilities for global and plywise failure analysis.


Advanced Failure Analysis

Crack growth simulation based on VCCT is available to simulate interfacial delamination.

Progressive damage is suitable for determining the ultimate strength of the composite (last‐ply failure analysis)

2D laminar composite

Initial crack

Start of damage (layer 1)

Progressed damage (layer 1)

Progressed damage (layer 3)


Customization

ANSYS Design Assessment


Motivation

Many of you have expressed the need for:→Computing and displaying specific results→Be able to achieve more complex “User defined results”


What is Design Assessment?

The Design Assessment system enables the selection and combination of upstream results and the ability to optionally further assess results with customizable scripts


Expanded Result Access

Filtering of potentially invalid combinations can be suppressed to enable greater user control. This allows the user to access results not typically available in the base analysis.

Modal=No Beam Results

DA + “Allow all Available Results” allows beam results


Design Assessment for Advanced “User Defined Results”

Design Assessment enable users to extend user defined results capabilities with:

→Expressions using mathematical operators as supported by Python

→Coordinate systems, Units Systems

→Integration options

→Nodal, Element‐Nodal & Elemental result types

→Import from external tablesScript used to display scalar element data stored

in an external file


Thin Structures

Mesh Connections


Motivation

In order to connect meshes of different surface parts so as to merge nodes at intersections, users do not always want or cannot merge the topologies at the geometry level. Mesh based connections are required.


Mesh Connections

Mesh connections work at part level:→As a post mesh operation→Base part mesh is stored to allow for quick changes in connections


Modal Analyses Shows Proper Connections of the Various Bodies


Contact Analysis

Rigid Body Dynamics


Motivation

Many mechanisms and assemblies have components that operate through contact.

In order to maintain the rapid turnaround for RBD simulations, there has been a subsequent focus on improving speed, accuracy and reliability of the contact capability.


Performance Improvements

Valve: 158 sec elapsed time (2x speed up)

Piston: 9 sec elapsed time (7.5x speed up)

The applicability, robustness and efficiency of the contact has been improved for speed and accuracy –expect a typical 2‐5x speed‐up

Transition and “jump” prediction have been greatly improved


Contact Analysis

Flexible bodies


Motivation

While already providing leading edge technology, ANSYS continues to enhance its ability to robustly and efficiently solve complex contact problems


Projected Contact

Improved pressure results with surface projection

The Surface Projection Based Contact provides more accurate results (stresses, pressures, temperatures) and is now also available for bonded MPC contacts

Regular contact Projection based

Smoother temperature results on a multilayered structure


Contact accuracy and robustness

Contact stabilization technique dampens relative motions between the contact and target surfaces for open contactNew contact

stabilization prevents rigid motion

“Adjust to touch” causes rigid body motion and leaves a gap


Performance

Further benefits from GPU boards


Taking advantage of the latest hardware is mandatory to solve your large models.

A combination of relatively new technologies provides a breakthrough means to reduce the time to solution

Motivation

+


Distributed ANSYS Supports GPUs

2.1 MDOF, Nonlinear Structural Analysis using the Distributed Sparse Solver

GPU Acceleration can now be used with Distributed ANSYS to combine the speed of GPU technology and the power of distributed ANSYS


Speed‐up from GPU technology

Solder Joint Benchmark ‐ 4M DOF, Creep Strain Analysis

Results Courtesy of MicroConsult Engineering, GmbH

Linux cluster : Each node contains 12 Intel Xeon 5600‐series cores, 96 GB RAM, NVIDIA Tesla M2070, InfiniBand

MoldPCB

Solder balls


Speed‐up from multiple nodes with 1 GPU board per node

MoldPCB

Solder balls

Results Courtesy of MicroConsult Engineering, GmbH

1 node @ 8 cores no GPU

1 nodes @ 8 cores, 1 GPU

8 nodes@ 1 core, 8 GPU

2 nodes@ 4 cores, 2 GPU


Advanced Modeling

Material Models


Motivation

ANSYS provides a comprehensive library of advanced materials.

Some users however need even more advanced models to include complex nonlinear phenomena in their simulations.


→Anisotropic Hyperelasticity plusViscoelasticity for strain rate effects

→Hyperelasticity coupled with Pore Pressure element

→Shape Memory Alloy enhanced with superelasticity, Memory effect, New Yield Function, Differentiated Moduli (Austenite, Martensite)

→Holzapfel Model ‐ Capture the behavior of fiber‐reinforced tissue

Advanced Materials for Biomechanical Applications

‘Hydrocephalus’ analysis Hyperelastic material with porous media

Stent modeling using shape memory alloys


Nonlinear materials support for coupled field elements

Coupled field‐elements for strongly coupled thermo‐mechanical analysis now accounts for plasticity induced heat generation along with friction effects

Friction Stir Welding including heat generation due to friction and plastic deformation


Advanced Modeling

Advanced Methods


Motivation

The solver techniques available from our solutions allow to model complex phenomena.

In some cases, better or different techniques are required to improve the accuracy or the convergence of the models.


Advanced Nonlinear Methods

User can now perform:→Buckling from a nonlinear prestressedstate with dead loads (new subspace eigensolver)

→3D rezoning for very large deformations for a wider range of materials and boundary conditions.

Hot‐Rolling Structural Steel Analysis with 3‐D Rezoning

Buckling of a pre‐stressed stiffened container


Analyzing Fasteners under Large Deformations

Bolt pretension does not include large rotation effects.

With release 14.0, you can now use Joint Loads:→Lock joint at specific load step→Apply Pre‐Tension or Pre‐Torque load→use iterative PCG solver for faster runtime

Joint Element ‐ Stress appears without significant bending

Pre‐tension element ‐ Significant bending stress with large rotation


Coupled structures/acoustics simulations

Coupled problems are modeled more efficiently:→Quadratic tetrahedral acoustics elements→New acoustics sources→Absorbing areas→Enhanced PML formulation → Near and far‐field parameters


Moisture Diffusion

Moisture induces hydroscopic stresses and alters thermal stresses.

Coupled‐field elements allow to incorporate moisture effects in thermal, structural and coupled simulations.


Advanced Modeling

Explicit Analysis – 1:30pm Session


Geometry

Advances for Structural Engineers


Motivation

With every release, ANSYS improves the quality of the geometry tools available in Workbench in order to increase the quality of the geometric data.

Ease of use is also constantly improved to provide more efficient tools.


Mid Surfacing Improvements

Selection tolerance is available to handle face pairs in case of imperfect offsets.

Body thicknesses can be displayed on the model.


Usability Enhancements

Toolbars can be customized for easy and direct access to preferred features and tools.

Hot keys are also available for frequently used operations.


SpaceClaim Direct Modeler

“Preview sharing” allow to control topology sharing before transferring the model into Workbench.

“Multi‐face patch” option increases the quality of repairs for missing faces.

Regular patch

Multi‐face patch


And there is much more…


…check the Release Notes!


Think also of the “Technology Demonstration Guide”


Questions?

Documents

Improving Your Structural Mechanics Simulations … Your Structural Mechanics Simulations with ... ANSYS Workbench is ... Bolt pretension does not