Grid resolution for an airfoil with a Gurney flap
 

Hi,

I am simulating a 2D airfoil with a Gurney flap(which is a thin flap, extending on the suction side attached to the trailing edge perpendicular to the camber). I am using a quasi steady approach and using the K-E(k- epsilon) turbulence model with a standard wall function. Now for an airfoil with a Gurney flap 2 counter rotating vortices are set up behind the airfoil and one more vortex is set up between the flap and the suction side. The problem is that for resolving these three vortices a very fine mesh is required due to which the wall y plus values in this region drop well below the recommended value(30 for standard wall fn and 5 for enhanced wall treatment) Is the use of the turbulence model still justified since I want the Cl(coefficient of lift) from this simulation or is there any other way out?