Investigation on performance characteristics of dielectric discharge plasma actuator using pulsed-dc waveform

Abstract

Dielectric Barrier Discharge Plasma Actuator (DBDPA) is one of active flow control devices, which generates a wall-surface jet utilizing atmospheric discharge. However, the enhancement of the jet is indispensable for application to high Reynolds number flow because the flow speed is typically only up to several meters per second. In recently, it was reported that a Pulsed-DC voltage waveform can drastically improve the jet thrust (McGowan et al., 2016). In the Pulsed-DC waveform, the high DC voltage rapidly drops to zero and gradually recover. In the original idea, the DC high voltage is applied to the top electrode and the Pulsed-DC waveform is applied to the bottom electrode. In this study, firstly, we conduct experiments using the same method proposed by the previous study, and next, the DBDPA, in which the top electrode is powered by the Pulsed-DC waveform and the bottom electrode is electrically grounded, is investigated. Finally, we propose a new waveform which is a sinusoidal voltage with periodical pulsed-earthing. As a result, the DBDPA with Pulsed-DC voltage waveform cannot generate strong wall-surface jet, and on the other hand, the proposed waveform generates a significant jet. Even though its strength is the same magnitude as that by the simple sinusoidal waveform, it is confirmed that the jet thrust is enhanced at phases before and after the pulsed-earthing; the tentative thrust increment is up to 32 %.