Test on active control of airfoil dynamic stall based on trailing edge flap

Aiming at the increase of unsteady load and stall flutter caused by dynamic stall, test research focusing on the control of airfoil dynamic was carried out using an airfoil test model with trailing edge flaps. The test Reynolds number was Re = 7.0 × 10⁵, and the reduced frequency k = 0.097. Dynamic pressure measurement was used to analyze the influence of different oscillating phase offsets, amplitudes and equilibrium angles of attack of the trailing edge flap on the airfoil during dynamic stall. The results show that the trailing edge flap with continuous sinusoidal oscillation can alternately change the aerodynamic performance of the airfoil with the time interval of 1/2 of the oscillation period. When the phase offset between the trailing edge flap and airfoil model is 0°, the peak pitching moment can reduce by 54.9% and a larger oscillation amplitude of the trailing edge flap seems to achieve a better control effect of unsteady load, but stall flutter may appear when it is too large. The oscillation equilibrium angle of attack of the trailing edge flap can change the lift coefficient and aerodynamic damping.