Discussion Forum

Dear COMSOL Community,

In a instationary journal bearing simulation I want to evaluate the resulting stresses in the bearing shell.
Therefore i solve the reynolds equation on the journal bearing surface. In the structural mechanics module I use the resulting hydrodynamic pressure as a boundary load. Due to the external loading and the deformation of the structure the filmthickness becomes very small. In this case a contact force, which is simply a interpolation function dependent on the filmthickness, starts to act leading to a additional boundary load on the strucutre.

The problem now is that in the case of a structure without initial stress/strains the simulation converges.
When I now add initial stress by performing a mounting step before, the simulation converges as long as the contact force doesn't act.
I suppose that some solver tuning is necessary to handle this problem since the simulation works, when there is no initial stress.

I already looked up in the knowledgebase but no solver tuning there helped me further. The simulation runs with a fully coupled solver.
Has anyone suggestions how to handle this problem. I thought of using an explicit time dependent solver, but couldn't figure out how to set this one up properly.
A further idea is to use an adaptive mesh refinement. Also in this case I'm not sure how to set this up properly.

Any help is heartly welcome. Thank you and

best regards,
Philipp