One of the most common simulation questions we encounter from our customers would be “If I am using nonlinear contact in my static study shouldn't my entire analysis become nonlinear?”
The answer is No.
All contact problems are often considered non-linear by nature. But the type of analysis one should use to address contact problems depends on many factors such as loads, material boundary conditions, surfaces and more.
Let’s clarify what makes anything non-linear.
As a load changes with time, the behavior of the contact including stiffness changes as well. Stiffness changes due to different loads and usually exhibit large amounts of displacement greater than the linear static small displacement formulations and that is why contact is non-linear by nature. Once SOLIDWORKS determines the forces that arise due to contact, it propagates that force into your model to calculate displacements, strains, and stresses. How your contact forces affect your model depends on whether you are in linear analysis or a nonlinear analysis. To calculate contact and the forces that arise in that contact area SOLIDWORKS must do that non-linearly. From the forces the contact calculations generates, if you are using a static study, all behavior will be linearized. The effect of contact is essentially another force/load on your model. How that force or any force interacts and behaves with your model is an effect of your analysis type.