Background eddy diffisivity

sim

Hello, all.

I am using CFX4.3's standard k-e model for wind calculation and need to set eddy diffusivity as a background value. The formula I use is Nu=0.09*k^2/eps

However the value is nearly zero at any points. I would like to give more large value of eddy diffusivity to the background. Is there another way to do it?? So far, I have no idea how to set it.

If you experienced similar problems, please let me know.

Thanks very much, sim.