Unsteady velocity magnitude- DNS

Rohan

Hi all,

Im Rohan currently working in DNS of separation in shear layer. Im running a case using DNS in fluent. I got my grid very fine and I ran the case.

My domain is a rectangulat duct with wall at bottom, top outflow and inlet and outlet.

I ran the case for 2500 time steps to get the steady state and another 2000 time steps to get time averaged values.

The problem I encounter is that the Instantaneous velocity at the wall is not equal to zero which makes it difficult to find the separation point.

What could be the problem??? Is there something wrong with the boundary conditions???

Thank You Rohan