Internal Characteristics of Air-Supplied Plasma Synthetic Jet Actuator

Abstract

Conventional plasma synthetic jet actuators rely only on jet orifice for suction when functioning for long durations. A limited supplementary gas leads to jet velocity reduction and weakening of the flow control ability. Therefore, this study proposes an air-supplied actuator with a check valve externally connected to the cavity to improve its gas-supplying ability and jet performance. A quartz glass discharge chamber is developed to clarify the internal working mechanism of the air-supplied actuator. High-speed schlieren is employed to photograph the internal flow field of the discharge chamber. The results reveal that the inhalation airflow velocity of the jet orifice is doubled when the actuator is continuously working in the effective frequency band under the combined action of additional air supply from the check valve in the inhalation recovery stage. The gas pressure in the cavity is closer to the initial discharge state, discharge breakdown voltage is higher, discharge energy is stronger, and the process of gas expansion to generate a jet is less affected by the core defect of the heat source, thereby significantly increasing the jet velocity and saturation operating frequency of the actuator. The obtained results have important implications for the performance optimization of the air-supplied actuator.