Unstructured grids:

zxaar

I am writing a code based on SIMPLE method. I am following the approach mentioned by peric. I have been observing one thing, that when I use structured meshes I get good results, but as soon as I shift to unstructured grids, the solution becomes unstable after few iterations, say 10 or 15. if I stop the solution before 10 iterations and observe the velocity-pressure field, I can see that in some parts the velocities are just too high. The pressure field also do not resemble the correct values.

Perics books mentions that the problems could come on tet meshes and fluent�fs manual also mentions this thing that on tet meshes we can see this kind of behaviour. What both the sources do not mention is what is the cure for this problem.

Can anybody give me some suggestion for this problem. I am using segregated solver. Thanks in advance.