When you started your model creation, did you pick the steady-state form of the equations or the transient form of the equations ? If you picked the steady-state form, then try to solve a transient with these equations, perhaps that is causing the problem.
Also, look at manual setting on the solver scaling in the advanced tab. I use this routinely to stabilize the turbulent NS equations. The scale factor I use is typically the maximum absolute value of the variable. You could obtain that from your steady-state solution.
Also, look at manual setting on the solver scaling in the advanced tab. I use this routinely to stabilize the turbulent NS equations. The scale factor I use is typically the maximum absolute value of the variable. You could obtain that from your steady-state solution.