Thin airfoil subsonic Stall
 

I am analysing a supercritical airfoil at subsonic (Mach 0.2) conditions. I am struggling with determining the correct stall angle. Stall should occur at around 8.5 degrees with a sharp leading edge stall but my model shows a gradual trailing edge stall.

I have tried various turbulence models as well as considerable grid refinements but nothing seems to work.

Does anyone have any ideas/hints/tips? :confused::confused: