Abstract:
The DBD (dielectric barrier discharge) plasma synthetic jet actuator driven by a sinusoidal alternating current high-voltage power is a typical active flow control actuator, which has the advantages of simple structure, flexible placement, and short response time. It has potential application prospects in lift enhancement and drag reduction, vibration suppression and noise reduction of aircraft, anti/de-icing. The plasma synthetic jet actuator consists of two traditional asymmetrical DBD plasma actuators which produce two wall jets. Under the interaction of the two induced wall jets, the plasma synthetic jet actuator generates a vertical upward jet, leading to promote the mixing between high-energy mainstream and low-energy airflow in the vicinity of the wall and achieve flow control. To understand the spatial-temporal evolution process of the flow field induced by the plasma synthetic jet actuator in-depth, the induced flow field was studied in quiescent air by using the time-resolved PIV (particle image velocimetry) technology. The plasma actuator was placed in a plexiglas box (600 mm in width × 600 mm in height and 800 mm in length) during the PIV experiments to ensure that the flow field produced by the plasma actuator was not disturbed by the external environment. The spatial-temporal evolution process of flow field induced by the actuator was revealed, the oscillation phenomenon of jet induced by the actuator was observed, and the evolution mechanism of flow field induced by the actuator was elucidated. The results indicated that the flow field created by the plasma synthetic jet actuator undergoes three stages, namely the development of starting vortices, the interaction of the two jets, and the oscillation of synthetic jet. Meanwhile, the induced oscillation angle range of the synthetic jet can reach ±45 °. The present results lay a foundation for advancing the numerical simulation model and enhancing the control effect of the plasma synthetic jet actuator.