Comparison between Density and Velocity Fields in Burst Modulation of a Dielectric-Barrier-Discharge Plasma Actuator

Abstract

The flow field produced by a dielectric-barrier-discharge plasma actuator using burst modulation was experimentally investigated in quiescent air from two viewpoints: density and vorticity fields. A wide range of burst signal parameters were evaluated using particle-image velocimetry and background-oriented schlieren measurements. Four types of flow-field patterns were found: Type 1 was a wall jet, similar to continuous operation; Type 2 was a periodical, independent vortex moving along the wall surface; Types 3 and 4 demonstrated a feature wherein the periodic shedding of the vortex pair (primary and secondary vortices) occurred while moving over the surface. While Types 3 and 4 demonstrated a shared feature, they had different density and vorticity structures. The change of the flow-field pattern from Type 1 to Type 4 was triggered by a lower burst frequency and ratio, as well as a higher base frequency. In addition, the vorticity strength and density were strongly negatively correlated and depended on the rate of power consumption to generate one vortex.

Effect of Plasma Actuator Layout on the Passage Vortex Reduction in a Linear Turbine Cascade for a Wide Range of Reynolds Numbers

“…Dielectric barrier discharge (DBD) PAs [17] represent a novel active fluid control technique distinguished by its high-speed response, wide frequency bandwidth, uncomplicated structure, and lightweight design. Recent PA research has focused on separation control mechanisms [18], icing mitigation [19], the flow control of the NACA0015 airfoil [20], the development of a background-oriented schlieren (BOS) system [21], density and velocity fields in burst modulation [22], cross-flow vortex cancellation [23], shock wave/boundary layer interaction [24], 3D turbulent boundary layer separation control via multi-discharge PAs [25], and closed-loop cavity shear layer control [26].…”