Effect of Plasma Actuator on Velocity and Temperature Profiles of High Aspect Ratio Rectangular Jet

Abstract

The turbulence jet centerline velocity and temperature decay intensely along the centerline flow direction. Thus, improving it could benefit engineering applications, such as air conditioners. However, active flow control techniques with high-aspect-ratio jets, especially for controlling the temperature, have not been widely investigated. This paper presents the velocity and temperature performance of a high-aspect-ratio rectangular jet controlled by two dielectric barrier discharge plasma actuators located on the longer sides of the nozzle and controlled by high-voltage and high-frequency pulse-width modulation sinusoidal waves. The scanning method was used to cover 362 cases as combinations of working parameters (modular frequency vs. duty vs. phase difference) for the velocity and temperature performances of the jets. Results show that plasma actuators can control both velocity and temperature distribution with minor input power compared with the rectangular jet’s kinetic energy and heat flux. The velocity increased up to 4% and decreased to 11%, measured at the interest position where x/h = 70 on the centerline. There were a 5% increase and a 4% decrease compared to the temperature-based case. Distinctive velocity and temperature distributions were observed under noteworthy cases, indicating the potential of the actuator to create various flow features without installing new hardware on the flow.