Is there a gap for eddy viscosity distribution in the wake ? when i use structure c grids,there is.but my classimate using unstructured grids got a no-gap result,why?

Hi,

wake of C grids is singular line. Usually, we use wake line BC as averaged value of nearest grid points. ie. suppose wake line are j=1,jmax,

q(1)=q(jmax)=0.5*(q(2)+q(jmax-1))

best regards

kei-tee

Thank you very much. I just do as you said .but there is a gap in the wake ,I don't know whether it is right.

What kind of Turbulence model do you use? Some model needs special treatment for wake BC.

i use k-epsilon,k-omeg & other use spalart.

S-A needs wall distance. In wake region, you should take the value as large value (ex. 1.0E6).

I don't know for k-eps & k-omega.

As long as you impose averaged value on Q vector & eddy viscosity in wake region, there is not a gap, I think.