2 Replies Latest reply: Oct 3, 2012 10:18 AM by William Crocker

    Large Displacement Analysis Failure

    William Crocker

      Hi guys!  I am having an issue where my assembly does not want to solve.  What I have is a lock ring that I want to compress.  I want to study the effect of adding relief holes in various locations/patterns to the stress throughout the ring.  The way I would like to do it is by creating a ridig body that has an ID located at the position I want the lock ring's OD and using a shrink fit between the external surfaces of the lock ring to the internal face of the rigid ring as shown in this picture:  http://i.imgur.com/lizwC.jpg.  I have large displacement on.  I have tried both fine and coarsh meshes.  I have tried both solvers.  But every time my solver fails.  When I remove the relief holes, the model does solve.  I am unsure what else I should try.

        • Re: Large Displacement Analysis Failure
          Bill McEachern

          Are you using the NL solver or the linear static solver? IF the latter why the large displacement option? Does it solve with out it on? Why do you want the cuts in the ring? The cuts will lower the force but I doubt they would lower the peak stress.

          If you use the NL solver, in my experience the shrink fit does not work too well. Better off to use a force to compress or expand hte flexible bit and hten relax it to get the fit. You need to do the expansion or contraction in one step to avoid getting hung up with interfrence on the contacts going the wrong way.

            • Re: Large Displacement Analysis Failure
              William Crocker

              I was using the linear static solver.  I was using the large displacement because the program asked me if I wanted to since it detect large displacement.  After some reading, I discovered that was not the right way to go.  I simply answered no to using large displacement and the problem solved (and behaves as expected).  Thanks for the help!