this problem is highly non-linear and solvingit in SWX sim which does not support self contact will be very tricky and quite time consuming. On the self contact you could get around hte limitation by split the can up into separate bodies - alonghte axial length. I frequency analysis maybe help full in sorting out how often you might do this. A non linear dynamic analysis may also be more help as the interia effects can help sort out the modes if a lot of things are buckling at once. You would be much better off witha code like Abaqus if youhave access to it. or an explicit code like LS-dyna.
have you tried what is recommended in the dialog? but like bill says, this is a pretty complicated problem.
what do you want to learn in this problem?