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zqnwpu June 25, 2003 22:22

eddy viscosity distributions in the wake?
 
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?

kei-tee June 26, 2003 09:38

Re: eddy viscosity distributions in the wake?
 
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

zqnwpu June 27, 2003 03:53

Re: eddy viscosity distributions in the wake?
 
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.

kei-tee June 29, 2003 04:12

Re: eddy viscosity distributions in the wake?
 
What kind of Turbulence model do you use? Some model needs special treatment for wake BC.

zqnwpu July 1, 2003 00:26

Re: eddy viscosity distributions in the wake?
 
i use k-epsilon,k-omeg & other use spalart.

kei-tee July 1, 2003 09:47

Re: eddy viscosity distributions in the wake?
 
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.



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