Table of Contents

www.kxcad.net Home > CAE Index > ANSYS Index > Release 11.0 Documentation for ANSYS

1. Design Optimization

1.1. Getting Started with Design Optimization

1.1.1. Design Optimization Terminology

1.1.2. Information Flow for an Optimization Analysis

1.2. Optimizing a Design

1.2.1. Create the Analysis File

1.2.2. Establish Parameters for Optimization

1.2.3. Enter OPT and Specify the Analysis File

1.2.4. Declare Optimization Variables

1.2.5. Choose Optimization Tool or Method

1.2.6. Specify Optimization Looping Controls

1.2.7. Initiate Optimization Analysis

1.2.8. Review Design Sets Data

1.3. Multiple Optimization Executions

1.3.1. Restarting an Optimization Analysis

1.4. Optimization Methods

1.4.1. Subproblem Approximation Method

1.4.2. First Order Method

1.4.3. Random Design Generation

1.4.4. Using the Sweep Tool

1.4.5. Using the Factorial Tool

1.4.6. Using the Gradient Evaluation Tool

1.5. Guidelines for Choosing Optimization Variables

1.5.1. Choosing Design Variables

1.5.2. Choosing State Variables

1.5.3. Choosing the Objective Function

1.6. Hints for Performing Design Optimization

1.6.1. Generating the Analysis File

1.6.2. Fixing Design Variable Values After Execution

1.6.3. Modifying the Optimization Variables After Execution

1.6.4. Local Versus Global Minimum

1.6.5. Minimum Weight Versus Minimum Volume

1.6.6. Mesh Density

1.6.7. Using Substructures

1.7. Sample Optimization Analysis

1.7.1. Problem Description

1.7.2. Problem Specifications

1.7.3. Using a Batch File for the Analysis

1.7.4. Using the GUI for the Analysis

1.7.5. Where to Find Other Examples

2. Topological Optimization

2.1. Understanding Topological Optimization

2.2. Employing Topological Optimization

2.2.1. Define the Structural Problem

2.2.2. Select the Element Types

2.2.3. Specify Optimized and Non-Optimized Regions

2.2.4. Define and Control Your Load Cases or Frequency Extraction

2.2.5. Define and Control the Optimization Process

2.2.6. Review the Results

2.3. A 2-D Multiple-Load Case Optimization Example

2.3.1. Problem Description - First Scenario

2.3.2. Problem Results -- First Scenario

2.3.3. Problem Description -- Second Scenario

2.3.4. Problem Results - Second Scenario

2.4. A 2-D Natural Frequency Maximization Example

2.4.1. Problem Description

2.4.2. Problem Results

2.5. Hints and Comments

2.6. Limitations

3. Probabilistic Design

3.1. Understanding Probabilistic Design

3.1.1. Traditional (Deterministic) vs. Probabilistic Design Analysis Methods

3.1.2. Reliability and Quality Issues

3.2. Probabilistic Design Terminology

3.3. Employing Probabilistic Design

3.3.1. Create the Analysis File

3.3.2. Establish Parameters for Probabilistic Design Analysis

3.3.3. Enter the PDS and Specify the Analysis File

3.3.4. Declare Random Input Variables

3.3.5. Visualize Random Input Variables

3.3.6. Specify Correlations Between Random Variables

3.3.7. Specify Random Output Parameters

3.3.8. Choose a Probabilistic Design Method

3.3.9. Execute Probabilistic Analysis Simulation Loops

3.3.10. Fit and Use Response Surfaces

3.3.11. Review Results Data

3.4. Guidelines for Selecting Probabilistic Design Variables

3.4.1. Choosing and Defining Random Input Variables

3.4.2. Choosing Random Output Parameters

3.5. Probabilistic Design Techniques

3.5.1. Monte Carlo Simulations

3.5.2. Response Surface Analysis Methods

3.6. Postprocessing Probabilistic Analysis Results

3.6.1. Statistical Post-Processing

3.6.2. Trend Postprocessing

3.6.3. Generating an HTML Report

3.7. Multiple Probabilistic Design Executions

3.7.1. Saving the Probabilistic Design Database

3.7.2. Restarting a Probabilistic Design Analysis

3.7.3. Clearing the Probabilistic Design Database

3.8. Sample Probabilistic Design Analysis

3.8.1. Problem Description

3.8.2. Problem Specifications

3.8.3. Using a Batch File for the Analysis

3.8.4. Using the GUI for the PDS Analysis

4. Variational Technology

4.1. Understanding Variational Technology for Parametric Studies

4.2. ANSYS DesignXplorer

4.2.1. What is ANSYS DesignXplorer

4.2.2. Systems Support

4.2.3. Basic Operation

4.2.4. Element Support

4.2.5. Limitations

4.2.6. Complete Discrete Analysis Example

4.2.7. Shell Thickness Example

4.2.8. ANSYS Mesh Morpher Example

4.2.9. Troubleshooting

4.3. Harmonic Sweep Using VT Accelerator

4.3.1. Elements Supporting Frequency-Dependent Property Structural Elements

4.3.2. Harmonic Sweep for High-Frequency Electromagnetic Problems

4.3.3. Harmonic Sweep for Structural Analysis with Frequency-Dependent Material Properties

4.3.4. Limitations

5. Adaptive Meshing

5.1. Prerequisites for Adaptive Meshing

5.2. Employing Adaptive Meshing

5.3. Modifying the Adaptive Meshing Process

5.3.1. Selective Adaptivity

5.3.2. Customizing the ADAPT Macro with User Subroutines

5.3.3. Customizing the ADAPT Macro (UADAPT.MAC)

5.4. Adaptive Meshing Hints and Comments

5.5. Where to Find Examples

6. Manual Rezoning

6.1. When to Use Rezoning

6.2. Rezoning Requirements

6.3. The Rezoning Process

6.4. Selecting the Substep to Initiate Rezoning

6.5. Remeshing

6.5.1. Selecting a Region to Remesh

6.5.2. Mesh Control

6.5.3. Contact Boundaries, Loads, and Boundary Conditions

6.6. Mapping Variables and Balancing Residuals

6.6.1. Mapping Solution Variables

6.6.2. Balancing Residual Forces

6.6.3. Continuing the Solution

6.6.4. Interpreting Mapped Results

6.6.5. Handling Convergence Difficulties

6.7. Repeating the Rezoning Process if Necessary

6.7.1. File Structures for Repeated Rezonings

6.8. Multiframe Restart After Rezoning

6.9. Postprocessing Rezoning Results

6.9.1. The Database Postprocessor

6.9.2. The Time-History Postprocessor

6.10. Rezoning Limitations and Restrictions

6.10.1. Rezoning Restrictions

6.11. Rezoning Example

6.11.1. Initial Input for the Analysis

6.11.2. Rezoning Input for the Analysis

7. Cyclic Symmetry Analysis

7.1. Understanding Cyclic Symmetry Analysis

7.1.1. How ANSYS Automates a Cyclic Symmetry Analysis

7.1.2. Commands Used in a Cyclic Symmetry Analysis

7.2. Cyclic Modeling

7.2.1. The Basic Sector

7.2.2. Edge Component Pairs

7.2.3. Model Verification (Preprocessing)

7.3. Solving a Cyclic Symmetry Analysis

7.3.1. Understanding the Solution Architecture

7.3.2. Supported Analysis Types

7.3.3. Solving a Static Cyclic Symmetry Analysis

7.3.4. Solving a Modal Cyclic Symmetry Analysis

7.3.5. Solving a Linear Buckling Cyclic Symmetry Analysis

7.3.6. Solving a Magnetic Cyclic Symmetry Analysis

7.3.7. Database Considerations After Obtaining the Solution

7.3.8. Model Verification (Solution)

7.4. Postprocessing a Cyclic Symmetry Analysis

7.4.1. Real and Imaginary Solution Components

7.4.2. Expanding the Cyclic Symmetry Solution

7.4.3. Phase Sweep of Repeated Eigenvector Shapes

7.5. Sample Modal Cyclic Symmetry Analysis

7.5.1. Problem Description

7.5.2. Problem Specifications

7.5.3. Input File for the Analysis

7.5.4. Analysis Steps

7.6. Sample Buckling Cyclic Symmetry Analysis

7.6.1. Problem Description

7.6.2. Problem Specifications

7.6.3. Input File for the Analysis

7.6.4. Analysis Steps

7.6.5. Solve For Critical Strut Temperature at Load Factor = 1.0

7.7. Sample Magnetic Cyclic Symmetry Analysis

7.7.1. Problem Description

7.7.2. Problem Specifications

7.7.3. Input file for the Analysis

8. Rotating Structure Analysis

8.1. Understanding Rotating Structure Dynamics

8.2. Using a Stationary Reference Frame

8.2.1. Campbell Diagram

8.2.2. Harmonic Analysis for Unbalance or General Rotating Asynchronous Forces

8.2.3. Orbits

8.3. Using a Rotating Reference Frame

8.4. Choosing the Appropriate Reference Frame Option

8.5. Sample Campbell Diagram Analysis

8.5.1. Problem Description

8.5.2. Problem Specifications

8.5.3. Input for the Analysis

8.5.4. Analysis Steps

8.6. Sample Coriolis Analysis

8.6.1. Problem Description

8.6.2. Problem Specifications

8.6.3. Input for the Analysis

8.6.4. Analysis Steps

8.7. Sample Unbalance Harmonic Analysis

8.7.1. Problem Description

8.7.2. Problem Specifications

8.7.3. Input for the Analysis

8.7.4. Analysis Steps

9. Submodeling

9.1. Understanding Submodeling

9.2. Employing Submodeling

9.2.1. Create and Analyze the Coarse Model

9.2.2. Create the Submodel

9.2.3. Perform Cut-Boundary Interpolation

9.2.4. Analyze the Submodel

9.2.5. Verify the Distance Between the Cut Boundaries and the Stress Concentration

9.3. Sample Analysis Input

9.4. Shell-to-Solid Submodels

9.5. Where to Find Examples

10. Substructuring

10.1. Benefits of Substructuring

10.2. Using Substructuring

10.2.1. Generation Pass: Creating the Superelement

10.2.2. Use Pass: Using the Superelement

10.2.3. Expansion Pass: Expanding Results Within the Superelement

10.3. Sample Analysis Input

10.4. Top-Down Substructuring

10.5. Automatically Generating Superelements

10.6. Nested Superelements

10.7. Prestressed Substructures

10.7.1. Static Analysis Prestress

10.7.2. Substructuring Analysis Prestress

10.8. Where to Find Examples

11. Component Mode Synthesis

11.1. Understanding Component Mode Synthesis

11.1.1. CMS Methods Supported

11.1.2. Solvers Used in Component Mode Synthesis

11.2. Employing Component Mode Synthesis

11.2.1. The CMS Generation Pass: Creating the Superelement

11.2.2. The CMS Use and Expansion Passes

11.2.3. Superelement Expansion in Transformed Locations

11.2.4. Plotting or Printing Mode Shapes

11.3. Sample Component Mode Synthesis Analysis

11.3.1. Problem Description

11.3.2. Problem Specifications

11.3.3. Input for the Analysis: Fixed-Interface Method

11.3.4. Analysis Steps: Fixed-Interface Method

11.3.5. Input for the Analysis: Free-Interface Method

11.3.6. Analysis Steps: Free-Interface Method

11.3.7. Input for the Analysis: Residual-Flexible Free-Interface Method

11.3.8. Analysis Steps: Residual-Flexible Free-Interface Method

11.3.9. Example: Superelement Expansion in a Transformed Location

12. Rigid Body Dynamics and the ANSYS-ADAMS Interface

12.1. Understanding the ANSYS-ADAMS Interface

12.2. Building the Model

12.3. Modeling Interface Points

12.4. Exporting to ADAMS

12.4.1. Exporting to ADAMS via Batch Mode

12.4.2. Verifying the Results

12.5. Running the ADAMS Simulation

12.6. Transferring Loads from ADAMS to ANSYS

12.6.1. Transferring Loads on a Rigid Body

12.6.2. Transferring the Loads of a Flexible Body

12.7. Methodology Behind the ANSYS-ADAMS Interface

12.7.1. The Modal Neutral File

12.7.2. Adding Weak Springs

12.8. Sample Rigid Body Dynamic Analysis

12.8.1. Problem Description

12.8.2. Problem Specifications

12.8.3. Command Input

13. Element Birth and Death

13.1. Elements Supporting Birth and Death

13.2. Understanding Element Birth and Death

13.3. Element Birth and Death Usage Hints

13.3.1. Changing Material Properties

13.4. Employing Birth and Death

13.4.1. Build the Model

13.4.2. Apply Loads and Obtain the Solution

13.4.3. Review the Results

13.4.4. Use ANSYS Results to Control Birth and Death

13.5. Where to Find Examples

14. User-Programmable Features and Nonstandard Uses

14.1. User-Programmable Features (UPFs)

14.1.1. Understanding UPFs

14.1.2. Types of UPFs Available

14.2. Nonstandard Uses of the ANSYS Program

14.2.1. What Are Nonstandard Uses?

14.2.2. Hints for Nonstandard Use of ANSYS

15. Using Shared-Memory ANSYS

15.1. Parallel Processing Methods Available in ANSYS

15.2. Activating Parallel Processing in a Shared-Memory Architecture

15.2.1. System-Specific Considerations