1 Reply Latest reply on Aug 26, 2014 10:56 PM by Jared Conway

    Thermal Load FEA question

    Daniel Genova

      I am working on a project in which I need to find whether a silicone rubber, which encapsulates a copper wire which is soldered to a circuit board, exerts enough force, when thermally expanding, to cause a failure in the copper wire or solder. The model I made includes a solder piece(which has a long cylindical piece to symbolize its insertion into a PCB board), and long copper wire, and a block of the silicone rubber.   The silicone rubber is fixed on all sides except the top and the whole assembly changes from room temperature to 85C.  However, I am confused on how to define the several boundary conditions.  

      1) For the thermal external load I applied it on every surface because the entire assembly eventually reaches 85C.  Should I instead have just applied it to the external surface?

      2) For for fixtures I defined all sides of the rubber , except the top, as fixed as well as the cylindrical part of the solder where the Circuit board would be

      3) For Connection's i bonded the copper wire to the rubber and the solder joint.

       

      Are these boundary conditions correct for the problem I defined?

      If the definition of the problem is too ambiguous let me know and I can try to rephrase it or provide more information.

      I have attached the file.

      Thanks!

        • Re: Thermal Load FEA question
          Jared Conway

          1) if you're just going with a static analysis, choose the bodies. if you need a temperature gradient, you'll need to start with a thermal analysis first.

          2) seems ok, but once you get it running you will want to try some experiments

          3) thats a good first step. most likely they are bonded in the real world.