Wind Tunnel Experimental Study on Dynamic Stall Control Using Wavy Leading Edges: Investigating Aerodynamic Performance and Flow Phenomena

Wavy leading edges significantly enhance the dynamic stall characteristics of the wing, but the underlying dynamic stall control mechanism is complex. To investigate the specific control effects of wavy leading edges and their unsteady control mechanisms, this study designs a wavy leading-edge wing (SC1094-A03L11) based on the SC1094 wing and conducts wind tunnel experiments using dynamic aerodynamic measurements and particle image velocimetry. Additionally, a control variable study is carried out focusing on the key parameters of reduced frequency and Reynolds number, which influence dynamic stall, to assess the effectiveness of the wavy leading edges in dynamic stall control. Examining the flow characteristics at four key sections of the wavy leading-edge wing serves to elucidate the dynamic stall control mechanisms. The results show that the wavy leading edges significantly improves the aerodynamic performance of the wing, effectively mitigating the hysteresis effects caused by large variations in angle of attack and notably suppressing flow separation on the wing surface. Under the test conditions, the wavy leading edges increases the average lift coefficient by 12.3%, reduces the maximum drag coefficient by 25.9%, decreases the area of the lift coefficient hysteresis loop by 47.7%, and delays the stall angle by 0.8°. The control variable study reveals that increasing the reduced frequency leads to an increase in the area of the lift coefficient hysteresis loop while diminishing the effectiveness of the wavy leading edges. In contrast, changes in Reynolds number have a relatively minor impact on the control effectiveness.