To calculate the frequency of the
structure for a load case, use the following procedure.
Frequency
calculation is made for a specific load case, so you must have at least one
primary load case added to the input file.
This can be done
by either the Rayleigh method or the eigenvalue extraction method. The latter
can consider missing mass mode.
-
Either:
The
Add New Load Items dialog opens.
-
Select either:
- the
tab to use the approximation method
- the
tab to use the more exact eigenvalue
extraction method
- Optional:
For Modal Calculation, check the
Consider Missing Mass option to include the
missing mass procedure for steady state or harmonic analysis.
-
Click
Add.
The frequency calculation is added to the load case.