u2.06.01 Implementation of a calculation of the natural modes of a structure

Summary

This document provides an overview of the various approaches available in Code_Aster to calculate the natural modes of vibration of a mechanical structure. These approaches are described starting from the simplest to implement, for standard studies, and gradually moving towards more elaborate implementations for advanced studies.

The necessary combinations of Code_Aster operators are presented, without going into the details of each operator.

• 1. Reminders: formulation of the problem
• 2. Problem data
• 3. Calculation of the natural vibration modes of a structure
  • 3.1. Simplest studies
  • 3.2. More advanced features
• 4. Parameters contained in a modal calculation result
• 5. Clean mode post-treatments
  • 5.1. Visualization
  • 5.2. Normalization of modes
  • 5.3. Filtering modes according to a criterion