A question about cyclic symmetry modal analysis

[Lirock]

Hi,everyone:
I tried to do a cyclic symmetry modal analysis according to help file.But didn't make it.I don't know where is the problem.Here is my steps:
1) BUILD THE FINITE ELEMENT MODEL, INCLUDING BUILDING GEOMETRY,MESHING,ROTATING THE NODE COORDINATE,AND DEFINE MATERIAL PROPERTIES
2)ISSUE COMMAND 'CYCGEN'
3)DEFINE ANALYSIS TYPE (MODAL ANALYSIS),DEFINE NUMBERS OF MODE TO EXTRACT, DEFINE BC.
4)ISSUE COMMAND 'CYCSOL'
Can anybody help me ?

 

[doatis]

Is 'cycgen' a typo? I can't find that listed in the ANSYS help manual anywhere.

Anyways, there is an example cyclic-symmetric analysis in the manual. If you go to:

Advanced Analysis Techniques > Cyclic Symmetry Analysis > Sample Modal Cyclic Symmetry

you will find a script that builds up, solves, and post processes an example.

Hope this helps,
Doug

 

[cbrn]

Hi,
just a general hint about modal analyses: take extreme care in performing cyclic modal analyses, as the modes extracted in this way may NOT cover ALL possible modes of the structure (this matter is more general than this: only the analysis performed on the whole structure can theoretically capture ALL modes): only the modes whose form can be described in terms of Fourier decomposition can be calculated like that, and provided that you investigate several cyclic indexes (0, 1, 2 at the very least, generally).
Of course, cyclic index can be fixed to a single value if you already know the form that the eigenvector of interest should take.
As for the command to set up a cyclic analysis, normally it's CYCLIC,...

Regards