Modelling solidification with turbulent flow

Feng Yun

Hello, Dear all, In Fluent, when I simulate the solidification with turulent flow, it is very difficult to obtain the convergent solution although I have carefully checked the grid adn y+ and reduced the under-relaxation factors. The message always shows the turbulent viscocity exceeds the limits. Could you give some suggestions about how to deal with this problem. Thank you for your help.