i have a problem in modelling jet flow through cascade. if the cascade has a super high angle of attack the fluid will separate in front of the cascade and it causes deflection stream after the leading edge.Besides that the fluid changes phase when the separation happened. So please gimme some advices how to model it.thanks anyway

(1). Before I can give you any suggestions, I need to know whether you are running test or simulation first. (2). Then try to describe the computational domain and the boundary conditions more clearly, I think it would help the reader to answer your questions. (3).Normally, flow separation is just change in flow pattern. Phase change in flow field could be related to the fluid condition at the inlet. If you specify the air at the inlet, then you are not going to see the phase change. (4). My suggestion is: try to simulate the flow through the cascade at the small angle of attack first. Then try to see whether the result is acceptable or not. After that, you can increase the angle of attack to this super high value, and run the simulation.