I was wondering what of the many things can cause a solution to not converge. The only problem that exists within my mesh is internal angles being too large or too small. Is it then a case of these internal angles, or does it have to do with the boundary consitions? My mesh is not very uniform either - it was created from some connecting blocks, which have various grid densities to account for geometry - could this be the cause? Sorry for the long message.

The general situation of the mesh is always a very immportant factor of divergence in CFD. There are additional reasons but in your case I think it's the mesh. What equations exactly are you solving and what relaxation factors are you using?

Heloo,

I'm also have the same prob with that,block meshing..i using UD equation n than restart with MARS after several iteration to stabilize it.

Cracks and couple may also cause it.