Turbulent boundary layer separation control using plasma actuator at Reynolds number 2000000

An experimental investigation was conducted to evaluate the effect of symmetrical plasma actuators on turbulent boundary layer separation control at high Reynolds number. Compared with the traditional control method of plasma actuator, the whole test model was made of aluminum and acted as a covered electrode of the symmetrical plasma actuator. The experimental study of plasma actuators' effect on surrounding air, a canonical zero-pressure gradient turbulent boundary, was carried out using particle image velocimetry(PIV) and laser Doppler velocimetry(LDV) in the 0.75 m × 0.75 m low speed wind tunnel to reveal the symmetrical plasma actuator characterization in an external flow. A half model of wing-body configuration was experimentally investigated in the  3.2 m low speed wind tunnel with a six-component strain gauge balance and PIV. The results show that the turbulent boundary layer separation of wing can be obviously suppressed and the maximum lift coefficient is improved at high Reynolds number with the symmetrical plasma actuator. It turns out that the maximum lift coefficient increased by approximately 8.98% and the stall angle of attack was delayed by approximately 2° at Reynolds number2 ×10～6. The effective mechanism for the turbulent separation control by the symmetrical plasma actuators is to induce the vortex near the wing surface which could create the relatively largescale disturbance and promote momentum mixing between low speed flow and main flow regions.