Discussion Forum

Hi everybody,

I'm using comsol a lot for one of my project (only solid mecanics tool).
I already read a lot in the forums, saw many official and unoficial video's about comsol. And i make a lot of tutoriels proposed by comsol to understand everything.

I'm stuck in one of my models.

The geometry is really simple (see attached file). It consist of 2 aluminiums sheets and 1 polymer sheet (the center sheet is made of polymer).
My first program was to set a point load on the upper right corner to see déformation. It worked well but it doesn't describe what really happen.
I want to have free rotation at my point load. So i delete a circle from the upper aluminium sheet, i create an aluminium circle with the right dimensions and i use form assembly. I create pairs between the sheet and the circle (both made of aluminium) and i set a load on my circle.
So i use my litle circle to move the rest of the geometry by contact.

As boundary condition, i only put the lowest segment to 0 displacement. (continuity is made between the 3 sheets).

This discribe very well the real case but i have convergence problem. Comsol is not able to run this simple simulation and i was surprised. Because it is 2D simulation with a simple geometry.

I have some results (so i know what i'm doing is right and this is what i really want) but they are useless because the simulation stop before reaching the end of calculation.

- I already put the discretisation in linear, i already try to play with the solver (coupled-fully segregate // tolerance - number of iterations - newton constant or automatic) it sometimes help a little but none were able to run until the end my simulation.

If somoene can help me to give me advice for the solver, or if you have another solution to get a free rotate load, it would be great.

Sory for my English which is not perfect.

Sébastien