Temporal Force Measurements on an Aerodynamic Plasma Actuator

Abstract

In previous work at the United States Air Force Academy, the phenomenology and behavior of the aerodynamic plasma actuator (a dielectric barrier discharge (DBD)) has been investigated. In order to provide additional insight into the phenomenology associated with the transfer of momentum to the air by the plasma actuator, the time-averaged body (reaction) force and the temporal force have been measured for a range of frequencies (5-20 kHz) and voltages (7.5-10 kV amplitude). The time-averaged forces were measured with a pendulum arrangement. The time-dependent forces were measured using an accelerometer. The results show that for constant voltage, the body force is proportional to frequency and the impulse per cycle is constant. Furthermore the energy dissipation per cycle and efficiency are independent of frequency. At constant frequency the increase in body force with voltage is shown. The time-dependent measurements support the theory that the body force of the actuator consists of one large PUSH followed by one small pull during each cycle.