Experiment for improving aerodynamic performances of a flying wing by millisecond pulsed plasma actuation

The experiment for improving aerodynamic performances of a flying wing by millisecond pulsed dielectric barrier discharge (DBD) plasma actuation was performed in a wind tunnel at incoming speed of 30 m/s. Plasma actuator was planted along the leading edge of the flying wings; the discharge energy of each pulse was at the order of 0.1 mJ/cm when the peak-to-peak voltage was 9.5 kV. The effect of actuation frequency and duty cycle on the aerodynamic performances, such as lift/drag coefficient, lift/drag ratio and pitch moment coefficient, was investigated through force measurement by a six-component balance. The results show that the aerodynamic performances of the flying wing at high angles of attack can be improved with plasma actuation. When the optimum non-dimensional actuation frequency F⁺≈1, the stall angle of attack increases from 14° to 17° and the maximum lift coefficient increases by 10%. The duty cycle plays an important role in flow control efficiency. The best duty cycle is 5% in the current investigation, which can reduce the power consumption tremendously. Meanwhile, the changes of pitch moment coefficient indicate that longitudinal static stability of flying wing is improved by plasma actuation.