3 Replies Latest reply on Apr 13, 2018 12:42 PM by Tyler Nichol

    Static Simulation with prescribed displacement, unrealistic results due to model fixtures

    Tyler Nichol

      Hello all,

       

      I'm hoping someone can help me with a problem I'm having using SolidWorks Simulation Standard 2017. I have a stud which is stretched to a known displacement and I want to find the stresses in the stud when stretched. I've cut out one-quarter of the stud along planes of symmetry, fixed the part with sliding constraints on the cut-planes and on one surface which is normal to the stud axis, and used a reference geometry constraint to displace the corresponding surface (also normal to stud axis, on other side of the stud).

       

      Sliding geometry: Highlighted surfaces constrained to in-plane displacement

      bitmap.png

      Prescribed displacement: Highlighted planar surface translated normal to plane, not constrained in other directions.

      bitmap.png

      The two constrained surfaces which are normal to the stud axis represent the portion of the part which is in contact with the mating components, which are loading the part.

      The results I get look like this:

       

      Right at that discontinuity we are getting stresses that are too high, but the results don't look accurate in that region (I would expect a single concave curve originating at the interface between the constrained surface and the adjacent surface, not an s-curve like this).

       

      Can anyone shed light on this? Does anyone know a better way to constrain the part to get results that more accurately reflect material mechanics?

       

      ***Edit***

      To add more color to this issue, I changed the constraints to apply only to the edge created by the split line instead of the whole contact surface and I get this:

      That outer edge (top of the figure) should have displaced about as much as the edge to which the prescribed translation was applied, no?

       

      ***Edit***

      Attached a mock-up file illustrating the issue