Can one of you who frequently refers questions to a page in one of the manuals tell me where I can find information about how closely the grids need to match at a GGI domain interface? I'm having some convergence issues and I'm wondering if it is because the grid spacing mismatch between the grids is too large at the interface.

Thanks,

Tristan

The grid of the two interfaces should be as equal as possible, but what kind of problem did you get? What do you mean with "convergence issue"? Of what type? Does the analysis stop? does the mass imbalance remain high?...

I've ever encounter the same problem. The tetra grid is about 3-4 times of hex grid. Also the convergence is not good. The pressure fluctuate heavily. After remesh the grid and made the two kind of grid uniform, this means the two of approximately same size. The oscillation disappeared.

This is probably more to do with the volume mesh than the surface mesh density difference at the interface.