I have a model that consists of two squares that are one on the other separated by 10 mm. The bottom square measures 60 mm, is pine wood with tangential behavior (with a poisson coefficient of 0.3) and has a fixed constraint on the lower edge. The above square is 40 mm, it is made of structural steel (material pre-configured in Comsol) and is centered on the lower square, to which a prescribed displacement is applied with the value of "-f * max" where the value of max is 10 mm and the value of f varies between 0 and 1.5.

A contact pair is defined between the upper edge of the steel square (source) and the upper edge of the wooden square (destination).

The mesh consists of free triangles with a size defined as "finer" and it is calibrated for general physics, and the edge defined as "destination" is "extra fine" in size.

In the study, an auxiliary sweep is configured with parameter f and the maximum number of iterations per segregated group is 60.

When giving the model to execute, it gives me a series of warnings which say: In the segregated group 1: There was an error message of the linear resolver. The relative error (8.9) is greater than the relative tolerance.

I do not know how to resolve these warnings would appreciate any help

excuse my english