3D Turbulent Boundary Layer Separation Control by Multi-Discharge Plasma Actuator

Abstract

In a subsonic wind tunnel, a three-dimensional separation of a developed turbulent boundary layer was simulated on a swept wing flap model. A multi-discharge plasma actuator operating on the basis of dielectric barrier discharge was used to overcome the positive pressure gradient, leading to a three-dimensional separation, when the ultimate streamline on the aerodynamic surface turns along the flap trailing edge. The actuator created an extended streamwise region of volume force, leading to flow acceleration near a streamlined surface. The influence of the force impact direction relative to the flap trailing edge was studied. The experiments demonstrated that the plasma actuator can significantly influence the flow structure in the separation region, leading to a decrease in both the transverse size of the viscous wake behind the flap and the total pressure losses within it.

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].…”