A large interval plasma synthetic jet actuator (PSJA) with multiple slots under low pressure condition was designed to control the flow-field for high-altitude vehicle.Since the breakdown voltage decreased rapidly under low pressure condition

the distance of cathode and anode can be extended to 26mm

much larger than that of traditional PSJA. This optimization also could make the cavity and output of actuator extend remarkably. The discharge characteristics and flow-field were researched by electric parameter measurement system and high-speed schlieren technology

respectively.The results showed that the initial jet velocity of the actuator reached 761m/s

indicating the actuator had excellent application prospect in high speed flow control.In addition

comparing with the normal perforated jet generated by the actuator

the compression wave and plasma jet appeared in an ellipse shape with a large flat portion

contributing to enhance the perturbation and momentum exchange capability.