Experimental Characterization of the RailPAc Plasma Flow Actuator

Abstract

An experimental study is conducted to characterize the development of a novel magnetohydrodynamic plasma actuator for aerodynamic flow control. The actuator is composed of two parallel rail electrodes embedded chord-wise on the surface of an airfoil. Self-induced electromagnetic fields force a low-voltage, high-current, pulsed arc along the length of the electrodes. The repetitive pulsed arc travels at high velocities, transferring momentum to the surrounding air, creating a high-velocity pulsed air wall jet. To quantify the physical characteristics of the plasma flow, the actuator is surface mounted on a flat plate test article and a cambered airfoil to measure the electrical properties, perform highspeed flow visualization, and measure the flow velocity induced by the plasma discharge. The experimental results demonstrate that the plasma arc requires discharge energies on the order of 300 J per pulse to achieve a peak arc velocity of 100 m/s. Wind tunnel tests on a 14.5 inch chord airfoil section, at a Reynolds number of 4.5 x 10 5 show a mean velocity of 20.5 m/s induced by the pulsed arc.