Does anyone have an idea why my model might not be running? [COMSOL]

[tugni925]

I am modelling a unit cell for a repetitive structure and then running a cell periodicity study to find the material properties. I have a model which gave me the correct output with another geometry, but with changed geometry I get this error:

The main thing I change in the model is the thickness (a) and length (l) of the "beams".

I have calculate the dimensions based the volume fraction of 0.2.

Please let me know if I can provide more pictures

 

[FEA way]

This looks like a generic non-convergence error. It’s hard to say more without knowing the settings of this analysis but I would start from checking boundary conditions.

 

[engineering_patrol]

check stiffness matrix.

 

[drennon236]

FEA way I have attached what I found under Fixed Constraint, tried to place it around the model but didnt seem to help much.

engineering_patrol, do I need livelink Matlab to see this stiffness matrix?