hello experts Does any one have experience in acoustics. I want to predict the sources of sound in closed duct (exhaust pipe)and i should also comsider the surrounding air.I tried to take mass flow rate as inlet B.C. I have modelled a small box outside the pipe and given a constant pressure. this B.C is phyical. I am using PISO algorithm. The problem is the rate of convergence of residual pressure is very very low.Any suggestions to improve convergence .Some suggestions on sources of sound are highly appreciable. regards kkreddy

The easiest way to go about starting this problem is to use the linearised N-S eqn about mean flow and then using some implicit or explicit schemes to solve the problem. This would speed up the solution .I have found compact schemes or DRP to run pretty faster .

-H

hi harish can u ellobate about compact schemes in brief.What is DRP.please explain in detail. thx..kamesh