Pro/Mech. Simple Question

[mothuproe]

Hi all,


I am new to Pro/Mechanica. Could you help me with the following?


I am doing a simple static structurealanalysis on an assembly.


It has three parts one over another. I am fixing the bottom part and applying load on the top surface of the top part.


Question: Do i need to create contact regions between the contacting surfaces of parts? without contact regions it is considering as if all three parts are stuck together. Withcontact regions, I saw the parts penetrating one into another( when i increase the deformation scale).


I would appreciate any posting on this problem.


Thanks


Srikanth