Active flutter suppression on a flexible wing via leading-edge blowing and circulation control

Abstract

Flutter is a classical aeroelastic phenomenon that seriously affects the performance of flexible wings. This study investigates flutter suppression through flow control for a flexible wing. Aerodynamic force, flow field, and dynamic aeroelastic response measurements are conducted to analyze the mechanism of flutter suppression through flow control on a flexible wing modified to include leading-edge blowing (LEB) and circulation control (CC) actuators around the wing tip. Furthermore, the flutter control effects of two control strategies, i.e., steady state control and proportion–integral–differential (PID) control, are compared. The results show that steady LEB and steady CC can effectively reduce the flutter amplitude and increase the critical flutter velocity. When the mass flow coefficient CQ≥1.46×10−3, the Coanda jet has better flutter suppression effect than the leading-edge jet. Moreover, a closed-loop CC control based on the PID algorithm demonstrates that PID control can effectively improve the flutter control efficiency. Compared to steady flow control, PID control increases the critical velocity by more than 52.60% and reduces the air consumption by 90.44%.