Computational and experimental study of the control efficiency of the flow around an airfoil by means of distributed mass transfer

The efficiency of stationary air blowing/suction into the turbulent boundary layer of the NACA 0012 airfoil through permeable sections located at the adjacent sides of the wing in the vicinity of its trailing edge is studied numerically and experimentally. The flow rates in these sections are varied in the intervals 0 ÷ 9.33·10 −4 and 0 ÷ 8.48·10 −4 , respectively. The studies are carried out at the Reynolds number Re c = 0.7·10 6 in the range of angles of attack α = − 6 ÷ 6°. The efficiency of the control method is estimated from the results of measurements using the original method proposed by Jones, based on traversing the wake behind the airfoil, and a modification of this method, as well as by using the results of numerical simulations. The necessity of the Jones formula modification is demonstrated to be particularly important in the case with individual suction and blowing because mass transfer through the surface changes the momentum transferred from the undisturbed external flow to the boundary layer.