OS-E: 0325 3D Rotor Dynamics Model

This example is about running a Frequency Response Analysis of a 3D rotor dynamics model using OptiStruct.

Figure 1. Model

Model Files

Refer to Access the Model Files to download the required model file(s).

The model files used in this example include:

  • rtr3dmodel.fem
  • runrtrdyn.fem

Model Description

The OptiStruct Rotor Dynamics feature currently supports only 1D rotors. To do the Frequency Response Analysis of the given 3D model, follow this 2 step process.
  1. Run a CMS analysis on the 3D rotor model to reduce it to a Superelement (DMIG). Use the file rtr3dmodel.fem. PARAM,COUPMASS,YES is used to get the accurate DMIG for gyroscopic matrix.
  2. Use the Superelement and attach to the 1D rotor model and run the Rotor Dynamics Analysis with the model file runrtrdyn.fem.
FE Model
Element Types
Linear Material


Figure 2. Driving Point FRF in the X-Direction