I am solving turbulent pipe flow with an explicit MacCormack scheme and Wilcox k-omega model. The laminar version of the code had three distinct stability criteria which worked fine after implementation.
Now, the turbulent version seems to have stability problem. I tried to upgrade the stability criteria for the new set of equations, but it seems that solution eventually blows up. I have noticed the omega values grow very large through all the domain.
Does anybody know if there are new stability conditions with k-omega model, or I should merely extend MacCormack stability to the new equations?
Also I appreciate it if anyone can introduce a paper or book that discusses two-equation models stability.