Turbulent Schmidt Number in SST model ?

David

There are some relations between the model parameters in SST model, such as beta_star/beta=1~1.25, alpha=f(beta,beta_star,sigma_w)..., but what the relations or how to determine the Turbulent Schmidt Number sigma_k and sigma_w, which control the diffusion rate of turbulence from higher-level regions to lower-level ones.

CFX gives the values sigma_k1=2,sigma_w1=2,sigma_k2=1,sigma_w2=1/0.856, but it does not explain how to get them. I try to change the set of the standard model constants to adapt my case, and I want to know the guide to determine these two important parameters. Thanks.