3 Replies Latest reply on May 18, 2010 2:12 AM by Ameer Chilakala

# Running a Non-Linear Study on Viscoelastic Material

Hello, I'm just looking for some advice on what improvements I can make to my model to get the results I'm looking for. We're modeling the compression of a themal pad under a normal load and we'd like to see the resultant deformation and stress distribution on the pad after compression. In order to model the displacement we had to come up with a fixture that would not hold the thermal pad in place, so we've sandwiched it between two aluminum plates in the model. I'm using a no-penetration contact with node-to-node contact types and the solution won't even get past the first step - it just freezes while calculating the number of contact points. What am i doing wrong? Is there a better way to restrain the thermal pad? Any help would be appreciated. I've attached my setup and a screencap of the problem.

• ###### Re: Running a Non-Linear Study on Viscoelastic Material

FYI: I'm running SolidWorks 4.1

• ###### Re: Running a Non-Linear Study on Viscoelastic Material

Hi

1 Geometry : You can cut out 3/4 of geometry and use Symetry to reduce number of elements and reduce total number of contact points,

2 Contact    :  Ensure if node2node definition is what you want. Isnt that so, that middle layer shall slide surface on surface to expand under given pression?

Regards

• ###### Re: Running a Non-Linear Study on Viscoelastic Material

Hi,

I checked your model, you did not applied proper boundary conditions for the parts.

You applied the normal load on the top plate, what about the constraints to that plate. if you are not applying any constraints means it can move in any direction.

you need to arrest the top plate remaining two directions i.e. allow the top plate move in downward direction only.

before running the nonlinear analysis, first solve the problem in static analysis with the applied boundary conditions. if its solving means then solve the same problem with nonlinear analysis i.e. changing the material, time curve etc.

kindly let me know if i am wrong.