Dear guys, I am having problem in convergence OF MASS.I have tried reducing uR etc. Let me give you a brief discription of the problem: My model is a big domain(50*12*8m^3) with a inlet header(dia=200mm having 200 holes) in it.The domain also consists of solid blocks in it. It is a conjugate heat transfe set up.The model does not show any error in check. I have specified inlet,outlet and wall B.C.

The flow is very less as compared to the size of domain.

Any previous experience with such type of problem??? TIA

In large problems I have done (>2 million cells) I need to use the AMG solver to get mass convergence.

Tom

Also, try to reduce time step and set the pressure correction relaxation factor to 0.8.

when i am giving AMG SOLVER,it is giving some error message and asking to contact ADAPCO. I DONT KNOW WHY???

tHANKS FOR THE RESPONSES.

The AMG sover is very sensitive to mesh errors. Use the check tool and check for connectivity, cracks, and centroid errors. Sometimes it works to restart from a run that was using the CG method.

Tom