Numerical Investigation of Suction/Blowing on Aerodynamic Efficiency of an Airfoil in Transient Flow Regime

The effect of the boundary layer and its local separation on the aerodynamic coefficients is one of the attractive topics for fluid mechanics researchers, especially in the analysis of the aerodynamic behavior of aircraft wings. Meanwhile, boundary layer control methods are commonly used for increasing aerodynamic coefficients. Boundary layer control is one of the important methods to improve the performance of airfoils. One of these methods is the suction and blowing the flow from the surface of the wings. In the present study, the turbulent fluid flow behavior of an e216 airfoil under individual and simultaneous suction and blowing in steady-state conditions were investigated using the k-ω SST model at Re=10 5. Initially, the variation of lift to drag ratio with angles of attack is validated with the existing experimental results and a good agreement is achieved, then the most appropriate case was found for the angle of attack 8 and three positions with different suction and blowing angles, then different angles of attack for cases with simultaneous suction and blowing were compared and acceptable results were obtained. By reducing the blowing speed and increasing the suction speed, the lift to drag ratio can be improved. Although in the present study, the inflow rate does not have a favorable effect, by decreasing the flow velocity, the lift to drag ratio improved and become close to one. In addition, the effect of blowing and suction is greater at higher blowing and suction angles and near the trailing edge of the airfoil.

Keywords:

Airfoil , boundary layer control , suction , blowing , CFD.