help for the oscillation of velocity!!!

dalton

Hi friends

I am using the colocated code to solve gas flow through the porous media. But the oscillation of velocity always occurs at the surface of porous media for both 1D or 2D cases.

This is the so-called infamous Rhie-Chow error. In CFX manual, the discussion is as following: "The rhie-chow term is damped at porous interfaces by multiplying by a factor which is small when there are large changes in porosity, and is near to unity otherwise".

I have already tried this method. It doesn't work. To my surprise !!!!, this problem exists for a long time. No open literature is good enough to discuss how to solve this problem.

Have you met this problem before? My treatment for face flux is following the Peric's method: Flux at face of node = Flux_averaging_from_the_ neighbours - pressure_drop_term_at_left_and right_node + pressure_drop_term_at_the_interface.

Are you using the colocated code? Have you some comments or suggestions on this problem.

Dalton