A self-trigger three-electrode plasma synthetic jet actuator

As a potential active flow control technology, plasma synthetic jet actuator (PSJA) has shown wide and promising application prospects in the high-speed flow. However, the application of PSJA is still limited by the low energy transfer efficiency and high driving voltage. This study presents a novel and practical self-trigger three-electrode plasma synthetic jet actuator (STPSJA), which is able to prolong the electrode distance with low breakdown voltage. A plasma jet is introduced to replace the high-voltage pulse of conventional three-electrode PSJA. The working process of STPSJA is investigated based on discharge waveforms, high-speed photography, and high-speed schlieren image system. Compared with the two-electrode actuator, the maximum precursor shock velocity can be increased from 449 m/s to 605 m/s. Furthermore, the discharge efficiency of STPSJA can be 68% when the electrode distance exceeds 10 mm and the breakdown voltage is only about 318 V. This study presents a promising step toward optimizing the design of plasma synthetic jet actuator.