Contact problem

[Naffoussi]

Hi all,

Im trying to perform a linear contact analysis on a cylinder with two bosses. these two bosses are fixed on a sleeves with four screws and there is a contact between these two parts.

Well, the cylinder is modeled using CQUAD4 elements. Bosses and sleeves are both modeled using CHEXA8 elements, with edgemembers on the bosses to allow the connection with the cylinder (rotations on plate elements). I also used RBE2 elements with C-BUSH on each side to represent screws between sleeves and bosses.

The CHEXA8 elements are associated to the geometry after revolving elements. i defined a face to face contact property between the sleeves and bosses.
when runing the analysis a message window appears "Model had errors and has not passed Rebuild, ok to translate?"

and the stress results are very high around the bosses and on the cylinder.
when i disable the contact and let the parts connected only with screws (RBE2, which is not realistic) i obtained reasonnable stress values.

any help?

see attached picture.