problem in gamma-retheta transition model
 

Dear friends;
I face the problem in applying Gamma-ReTheta transition model. based on what I understood, the problem stems from these two terms (vorticity and strain rate). in fact, the values of these two terms became too large, and since they multiple in some terms in source terms of intermittency , specially in the dissipation term, the value of dissipation in comparison to the production gains larger value and due to this reason, finally the code starts diverging. I used under-relaxation coefficient to make it more stable, but it diverges yet and only divergence is put off. I also used different convection descritization method such as QUICK, TVD (SUPERBEE, mid-mod, QUICK and van- leer limiters), but unfortunately, they can not fix the problem. I really appreciate it if anyone could guide me in solving the problem.