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Dear Sir

I am a Ph.D. student in Mosul University (Iraq)/Mech. Eng. Department. I am working on Boundary Layer Control on Airfoil using finite difference representation. I will be very grateful for you for any help.

The Grid generation which I building orthogonal C- type, according the below Ref. 1-Nearly Orthogonal Two-Dimensional Grid Generation with Aspect Ratio Control. J. Comp. Phys. 171, 2001. and 2- 2D orthogonal grid generation with boundary point distribution control, J. Comput. Phys. 125, 440-453, 1996). Then, I reached to a good C-Type grid generation about airfoil, please view the grid in the attached file (Fig.1).

Now, my problems are related to the solution of the 2D Incomp. subsonic flow on airfoil (Potential "initial for viscous" and viscous flow), more specific at trailing edge and also when give angle of attack for potential "which is initial for viscous" and viscous flow. The general Outline of my research and my problems: (Please, see the attached file where my problems are explained in more detail, also the results.) 1-2D orthogonal structure grid generation, C-type. (completed OK) 2-Potential flow which is initial condition for viscous. Solution Laplace equation of perturbation velocity potential. I think is my problem in trailing edge and the boundary condition on wake surface ( I cant understand how applied the Kutta Condition on trailing edge and the boundary condition on wake surface). Where all my results are OK in all points of mesh excepts on trailing edge point and wake region. 3-Viscous flow, same the problem is appear in trailing edge and wake region. Therefore, I think that the problem is coming from potential flow. (Please, see the attached file where my problems are explained in more detail, also the results.)

Thanks for any suggestion or opinion, with my best regards. .

Laith Mohammed Jasim Laith20042001@yahoo.com