Comparison of free component mode synthesis techniques using MSC/NASTRAN
MSC/NASTRAN was used to compare three techniques of component mode synthesis (CMS) using free modes. A free-free beam model was analyzed by the three methods and compared to the finite element results for the entire beam. The three CMS techniques use different combinations of assumed displacement vectors. Two of the techniques are available as standard options within MSC/NASTRAN. The third uses residual terms and is ideally suited to using results from an experimental data base to describe a portion of the model. For this technique, we studied the effects of including residual terms only in the stiffness matrix or in both the mass and stiffness matrices, as well as neglecting the off-diagonal residual terms. Significant divergence of low-frequency system modes was obtained when using one technique while excellent and identical convergence was obtained using the other two. Results are given for modal frequency convergence, mode shape correlation, and mode shape convergence.
- Research Organization:
- Sandia National Labs., Albuquerque, NM (USA)
- DOE Contract Number:
- AC04-76DP00789
- OSTI ID:
- 6683063
- Report Number(s):
- SAND-83-0025; ON: DE84014451
- Country of Publication:
- United States
- Language:
- English
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