10 Replies Latest reply on Jan 11, 2016 6:16 PM by Owen Boden

    Nonlinear compression of rubber spring - HELP!

    Owen Boden

      Hi all

       

      My first post here but a complex one, any help, pointers or tips would be greatly appreciated.

       

      I need to compress a large rubber spring, 1200mm long, dia 250mm. The material is Hytrel, I have created a custom material and I have loaded in the appropriate stress/strain data. I'm running the study as a 2D simplification as the part is symmetrical. The part is supported with a fixed geometry condition at the bottom of the spring and the load is 50KN simply acting as a compression force at top of the part.

       

       

      My goal is to compress the spring by 50-60% of its total length i.e.~600mm. The best I can get is 82mm compression before I get the 'Reduce the Singularity elimination factor (.5 or 0)' message. When I play with the Singularity Elimination value I get slightly better results but still nowhere near the 50% compression.

       

      I have experimented with both the Force and Displacement incremental control techniques using the Newton-Raphson iterative method.

      I have also tried local meshing but to no avail.

       

      I want to know if there is something more I can do or if I'm at the limits of the software?

       

      Many thanks

      Owen