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Example Guide
The OptiStruct Example Guide is a collection of solved examples for various solution sequences and optimization types and provides you with examples of the real-world applications and capabilities of OptiStruct.
Normal Modes Analysis
This section presents normal modes analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
OS-E: 0400 Compressor Wheel
OptiStruct was used to run a free-free normal modes analysis on a gas turbine compressor wheel solid FE model.

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Overview
OptiStruct is a proven, modern structural solver with comprehensive, accurate and scalable solutions for linear and nonlinear analyses across statics and dynamics, vibrations, acoustics, fatigue, heat transfer, and multiphysics disciplines.
Tutorials
Discover OptiStruct functionality with interactive tutorials.
User Guide
This manual provides detailed information regarding the features, functionality, and simulation methods available in OptiStruct.
Reference Guide
This manual provides a detailed list and usage information regarding input entries, output entries, and parameters available in OptiStruct.
Example Guide
The OptiStruct Example Guide is a collection of solved examples for various solution sequences and optimization types and provides you with examples of the real-world applications and capabilities of OptiStruct.
- Nonlinear Small Displacement Analysis
  This section presents nonlinear small displacement analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
- Nonlinear Large Displacement Analysis
  This section presents nonlinear large displacement analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
- Nonlinear Transient Analysis
  This section presents nonlinear transient analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
- Frequency Response Analysis
- Normal Modes Analysis
  This section presents normal modes analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
  - OS-E: 0400 Compressor Wheel
    OptiStruct was used to run a free-free normal modes analysis on a gas turbine compressor wheel solid FE model.
  - OS-E: 0405 Pre-load Analysis of Chair Frame
    Demonstrates the use of pre-loading with Normal Mode Analysis. Pre-Loaded Analysis is a type of structural analysis performed on a structure under prior loading (Pre-Loading).
- Complex Eigenvalue Analysis
  This section presents complex eigenvalue analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
- Thermal and Heat Transfer Analysis
  This section presents thermal and heat transfer analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
- Analysis Techniques
  This section presents analysis technique examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
- Topology Optimization
- Size (Parameter) Optimization
- Free-shape Optimization
- Shape Optimization
  This section presents shape optimization example problems, solved using OptiStruct. Each example uses a problem description, execution procedures and results to demonstrate how OptiStruct is used in shape optimization.
- Topography Optimization
  The examples in this section demonstrate how topography optimization generates both bead reinforcements in stamped plate structures and rib reinforcements for solid structures.
- ESLM Optimization
  The examples in this section demonstrate how the Equivalent Static Load Method (ESLM) can be used for the optimization of flexible bodies in multibody systems.
- Multiphysics
  This section presents multiphysic examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
- Rotor Dynamics
- Response Spectrum
  This section presents response spectrum examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
- Nonlinear Explicit Analysis
  This section presents nonlinear explicit analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
- Piezoelectric Analysis
  This section presents piezoelectric analysis examples generated using OptiStruct. Each example uses a problem description, execution procedures, and results to demonstrate how OptiStruct is used.
Verification Problems
This manual presents solved verification models including NAFEMS problems.
Frequently Asked Questions
This section provides quick responses to typical and frequently asked questions regarding OptiStruct.

OS-E: 0400 Compressor Wheel

OptiStruct was used to run a free-free normal modes analysis on a gas turbine compressor wheel solid FE model.

Model Files

Before you begin, copy the file(s) used in this example to your working directory.

compressor.fem

Model Description

A solid hexa model of a gas turbine compressor wheel with fins was generated with HyperMesh. The model contained 44,369 grids and 31,022 solid hexa elements. A free-free modal analysis was conducted using OptiStruct to find the first twelve natural frequencies.

Results

The first six frequencies found were rigid body modes and can be disregarded.

The frequency results are:

Model #: Frequency
7: 2.46
8: 2.46
9: 3.33
10: 3.62
11: 3.62
12: 3.83