ANSYS PLATES VIBRATIONS

[webroot]

Hello,

I have a question for an expert in Vibrations and ANSYS.
I am trying to get the natural frequency for vibrations of plates with varying thicknesses. My question is: Will I get accurate results if I used a SHELL 63 element to model a plate with varying thickness? Should I use a solid element instead of SHELL63 element? The results I got using SHELL63 element were quite good compared with the analytical reesults, althoug I am not sure if this was the right element for modelling a (3-D)plate with varying thickness.

Thank you very much.

 

[zuardy]

Hi,
I have done vibration (dynamic) analysis more in NASTRAN then in ANSYS, but I think this should be the same.
You are right, that you have modelled your plate with SHELL elements concerning numerical errorness, if it was modelled with SOLID, due to the greater number of DOFs. To take the thicknes variations in to account, you can use the average thikness per elements. If your plate is moderately-thick, then you may use SHELL43 to medell it.

regards

 

[FEMSOL]

Shell elements have 6 DOFs(ux,uy,uz,rotx,roty,rotz) whereas solid elements have 3 DOFs.(ux,uy,uz)
Therefore using shell elements over the solid elements will give you more accurate results.