Investigation of the interaction between NS-DBD plasma-induced vortexes and separated flow over a swept wing

Abstract

The effect of nanosecond pulsed dielectric barrier discharge (NS-DBD) plasma flow separation control is closely related to the actuation frequency, because it involves the interaction between plasma-induced vortexes and separated flow. In order to study the mechanism of NS-DBD plasma flow separation control over a swept wing, especially the influence of the actuation frequency, at first, experimental studies of the actuation frequencies at 100 Hz are conducted to validate the numerical simulation method. Then, numerical studies of different actuation frequencies which are 50 Hz, 100 Hz, 160 Hz, 200 Hz, 500 Hz, and 1000 Hz, respectively are conducted. The interaction between the plasma-induced vortexes and the separated flow is analyzed. Results show that there is a range of the actuation frequency which includes the frequency (160 Hz) calculated by the average aerodynamic chord length to make the control effect good, but when the actuation frequencies are too low (50 Hz) or too high (1000 Hz), the control effect will get worse. The former is because plasma-induced vortexes disappear in a period within an actuation cycle; the latter is because plasma-induced vortexes cannot develop completely, resulting in a weak vortex intensity.