低雷诺数下协同射流关键参数对翼型气动性能的影响

Co-flow jet is an efficient and novel active flow control technology. There is no systematic study on the influence of key parameters of co-flow jet on airfoil aerodynamic performance. By introducing the actuator disk model of propeller, a new method for simulation of the flow around the co-flow jet airfoil is developed, resulting in a more practical method for calculating the jet reaction force. Under the condition of low Reynolds number, the effects of key parameters, including jet momentum coefficient, opening size and opening location, on the aerodynamic performance of the NACA6415 airfoil are studied, and the corresponding physical mechanism is discussed. The results demonstrate that compared to the attached flow at small angle of attack, the influence of jet momentum coefficient on aerodynamic performance is more complicated for the separated flow at larger angle of attack. With the increase of injection size, the pump power coefficient decreases first and then increases, the effective lift to drag ratio increases first and then decreases. As the suction size increases, the pump power coefficient gradually decreases, and effective lift to drag ratio increases first and then tends to be stable. The location of the injection and suction has little effects on both the aerodynamic performance of the airfoil and the pump power coefficient.