Having problem with turbulent flow over a forward facing step
 

Hi,

I am using Ansys CFX for simulating a turbulent flow over a forward facing step. The Reynolds number is around 10000 and the step height is 9 mm. I did the grid study and the boundary conditions that I used are velocity at the inlet and zero static pressure at the outlet and no slip at the walls. I am comparing the performance of two different turbulence models (k-e, sst). The problem is that k-e can predict the length of the recirculation region at the top of the step with a vary good agreement with experimental results while SST predicts the length of the recirculation region twice the experimental results. I've read that k-e has a problem with separating and reattaching flows and cannot predict it well and I'm confused. Please let me know about your opinion in this regard.

Thanks