AERODYNAMICS OF AIRFOIL IN SHEAR FLOWS-A NUMERICAL STUDY

A Numerical Study has been carried out to determine the influence of shear flow parameters (shear spread (d), and the vertical orientation of the shear stream (ys)) on the aerodynamic coefficients CL and Cd. The results are obtained for a Joukowski Airfoil immersed in Gaussian exponential shear stream at Reynolds number of 20,000. In order to exclude the effect of the incoming stagnation pressure and study only the effect of the vorticity carried by the Gaussian shear stream, the aero-dynamic coefficients are calculated with respect to the dynamic pressure of the separating streamline at the Gaussian profile. The integro-differential formulation is used to solve the governing Navier-stokes eqdations. The results show that the Gaussian shear parameters(ys)and(d)have small influence on the aerodynamic coefficients. This conclusion recommend that the strong interaction between the vorticity carried by the shear stream and the circulation around the airfoil (predicted by the inviscid analysis) is considerably weakend by viscous dissipation.