[Satz]

Greetings,

I am simulating flow around NACA0012 Airfoil for different angle of attack (10 to 80) to determine Cl and Cd. I am using C mesh having appropriate computational domain based on literature. Velocity inlet is prescribed to C curve and sides while pressure outlet is used far downstream. I have simulated for 10 and 20 degrees for which the results agree with the experimental work. But for 30 deg case, REVERSE FLOW occurs in some faces of the domain. I would like to clarify my doubts,

1. Does reverse flow affects the accuracy of the results
2. What should I do to get rid of the Reverse flow problem?
3. If for some iterations the reverse flow exists and later disappears after some iterations, will that have effect on the results?

Enclosed Mesh file -Screenshot(105)