Dear Researchers,

I am conducting modal analysis simulation of a tiny assembly of more than 250 parts. I removed all the bolts used to fix parts together and closed the holes.

Then I used bonded contact at the interface between the surfaces where the parts are contacted (instead of the bolts). Hereafter, I conducted modal analysis with an assumed coarse Mesh and the natural frequencies were calculated. Then I tried to decrease the mesh element size to exclude the mesh dependancy BUT!!!!!. Decreasing the mesh size, the natural frequencies were also decreasing (1%-6%).

The question is: did any one of you faced such problem before? any advices to improve the FE model?

Best regards

Mohamed