Performance Improvements Of Plasma Synthesis Jet And Application In Active Flow Control

Plasma synthetic jet(PSJ)is applied to the active flow control of aircraft,which has the advantages of simple structure,low energy consumption,small size,light weight,flexible control,quick response and so on,that make it has a wide application prospect.In this paper,the research work on improving the performance of PSJ actuator,the application of plasma synthetic jet to active flow control,and the research and development of new plasma power supply have been carried out.Some valuable research results have been obtained.First of all,for the PSJ actuator with an one-way valve to replenish air,the flow dynamic pressure to enhance the one-way valve fill air efficiency to improve the jet velocity was imitated,so as to improve the performance of the actuator.To this end,an experimental platform was set up to imitate the flow pressure to fill the air in the actuator through the one-way valve.In the experiment,the inlet flow dynamic pressure at different speeds was simulated by adjusting the outlet flow pressure of the reducing valve and the influence of flow dynamic pressure on the actuator performance under different conditions was studied.It has been found that the simulated inlet flow can effectively enhance the average velocity of the jet,reduce the average power of the actuator and make the actuator discharge more stable.Secondly,PIV was used to study the active flow control effect of the PSJ on NACA0021 airfoil model in different positions along the flow direction and the span wise direction.The jets were respectively arranged at the leading edge stagnation point and facing the upstream direction,and on the airfoil upper surface which is 25%chord length from the leading edge and in downstream.The influence of the plasma synthetic jet on the upper airfoil flow has been studied,and the influence range of a single jet on the flow along the wingspan has been also explored.The results show that the leading edge jet has a better control effect on flow separation,and the jet has a control range of at least 80mm wide in the direction of wingspan.Finally,a new power source was developed for plasma synthesis jet.The triggering performance of Marx generator as power supply and the ability to drive a PSJ actuator were studied.Marx generator is triggered by high-voltage pulse signals of different frequencies.The performance changes of the PSJ actuator have been studied under different trigger conditions.And the jet velocity generated by high-voltage pulse power sources with the same power at the same frequency was compared.Experiments show that higher velocity jets can be obtained by using Marx generator.The research results of this paper have certain guiding significance for the further improvement and practical application of the PSJ actuator,and also verify the feasibility of Marx generator as the driving power of the PSJ actuator with controllable frequency,laying a foundation for further optimization.