Hi!
We recently installed COMSOL 4.2. (We've been using COMSOL 3.5a, so we are trying to create the same model on COMSOL 4.2. The model works with COMSOL 3.5a version)
Basically, I am working on "Transport of Diluted Species" module, where I want periodic condition from left and right of my slab of brick and mortar geometry.
I set my bricks to be impermeable by putting zero diffusivity, and I put a value for mortar geometry. And I set top mortar to have a certain concentration (infinite source), and I set the bottom mortar to have zero concentration (infinite sink). My brick and mortar is a 2D geometry, and I put periodic condition on left and right side of my rectangular slab. I basically want my solutes to go through mortar pathway, but for some reasons, it's not working on this model.
I guess I am doing something wrong, I got below error message from COMSOL 4.2
Undefined value found.
- Detail: Undefined value found in the stiffness matrix.
There are 253 equations giving NaN/Inf in the matrix rows for the variable mod1.c
at coordinates: (4.01e-005,1.75e-005), (4.01e-005,1.74437e-005), (4.01e-005,1.73683e-005), (4.01e-005,1.72675e-005), (4.01e-005,1.71327e-005), ...
and similarly for the degrees of freedom, NaN/Inf in the matrix columns
What am I doing wrong?