I'm running simulation on 3D circular chamber(20 mm section diameter x 100 mm in span). Inlet is through tube connected in the mid span (10 mm diameter) and on the opposite side there is slot cut (0.7 mm wide) that run along the span for the exit flow. I have to do both steady and unsteady simulation with constant pressure inlet and sinusoidal pressure inlet. Actually I have run steady simulation with second order scheme for pressure and momentum, K-Eps turbulence model with enhanced wall treatment(grid resolution is MAX yplus less than 3) and simplec for pressure velocity coupling. The problem is that convergence is quite good (10-6) for velocity and turbulence parameter, but continuity residual does not go under 10-4, remain steady...

is normal that continuity residual does not go under certain values or I can do something to improve results?thank you in advance bye, dario

Hi!

I think, thats ok... someone told me, sometimes, the continuity residual has to be under 10-3 and steady.

BUT one more interesting convergenz criteria is a point or surface monitor.

Create a point, that is in an area of high gradient of an intersting value (eg. velocity). Now, use report->monitor->surface and select the point and eg. average velocity.

Ralf