OptiStruct for Linear Analysis (5) Linear Bucking Analysis

1. Linear Bucking Analysis Setup

In this lesson we will discuss linear buckling analysis and how to set up an analysis using OptiStruct and HyperWorks.  Linear buckling analysis is a numerical method used to predict the theoretical buckling load of an ideal elastic structure.   Watch the video below to learn more.

What is Linear Buckling Analysis?

Thin-walled structures subject to compression and/or shear loads that haven’t reached the material strength limits can show instability.  Sensitivity to structural instability or buckling can be analyzed using linear buckling analysis.

Watch the video below to view an overview on Buckling Analysis.

Solution of Linear Buckling

The problem of linear buckling is solved in two stages:

1. A standard linear static analysis is carried out to obtain stresses, which form the geometric stiffness matrix. 
2. The buckling loads are then calculated by solving the eigenvalue problem.

A subcase requires a STATSUB card for a Buckling Analysis.

Linear Buckling Analysis Workflow

2. Exercise – Wing Linear Buckling Analysis

In this exercise we will start by loading a wing model in HyperWorks and running a baseline static analysis of the model as setup to understand the existing loads and loadsteps. Then we will create a load step input for the buckling analysis and one loadstep for each of the three subcases.  Finally we will run the analysis in the Compute Console and post-process the results in the HyperView client.

Watch the video below to view a demonstration of the exercise.  Then download the PDF and model files to do the exercise yourself!

Files:

• ex2c.pdf
• 2C.zip

 

Next: OptiStruct for Linear Analysis (6) Thermomechanical Analysis