Structure optimization of the AC-SDBD plasma actuator under duty-cycle mode

Abstract

Alternating current dielectric barrier discharge plasma actuators driven by steady and unsteady mode were experimentally optimized in a static atmosphere. The purpose of this optimization is to enhance the effective controllability of flow control. Electrical properties were evaluated using the measured voltage, current and power consumption data. The dielectric barrier with different materials was tested and the aerodynamic characteristics were identified by particle image velocimetry and electronic force balance. Meanwhile, the duty-cycle technique was applied to operate the actuator in unsteady mode. The dynamic characteristics of induced flow were analyzed by processing the results with the phase-locked method. The development of induced flow structure at different frequencies was compared. Results showed that the plasma actuator with 4 mm-thick Teflon dielectric barrier induced the maximum force and velocity of 75 mN/m and 5.6 m/s, respectively. The discharge frequency has little effect on the control authority at the kilohertz level. The dimensionless area of the induced flow is about [Formula: see text] under steady actuation. The phase-locked results confirm that the scale and strength of the induced vortex vary with the duty-cycle frequencies. The effectiveness of unsteady flow control can be explained as the promotion of the boundary layer and the mainstream.