I am performing a SRS analysis on a circuit board assembly that can have two very different boundary conditions during it's operation. In both scenarios, it is encapsulated in a silicone elastomer, and that encapsulated "brick" is fit into a metallic slot that engages about 10% of the brick's length. In one scenario, the encapsulated circuit board assy is encased in a polyurethane wax that covers about 1/2 of the encapsulated circuit board assy. In the other scenario, the wax has melted and the only retention that the encapsulated circuit board assy has is the light slip-fit in the metal slot. I've enclosed a JPG image to show the general construction. If the circuit board assembly does start to slip out of the slot, it can't go very far because there is a metal housing surrounding everything. My question is, is there any way to model the melted wax in the Premium Solidworks Simluation package? I have thought about trying to model it as a boundary condition, such as a "soft spring" condition, but I am not confident about that approach. Does anyone have suggestions or techniques that they have successfully used, or would I need to purchase a "multiphysics" package of some sort in order to model the melted wax contribution? I have done some research and found that it is very similar in viscosity and density to a certain diesel oil, so that gives you an idea of its properties.