A new electrical discharge called sliding discharge was developed to generate plasmaaerodynamic actuation for flow control.A microsecond-pulse high voltage with a DC componentwas used to energize a three-electrode actuator to generate sliding discharge.The characteristicsof plasma aerodynamic actuation by sliding discharge were experimentally investigated.Dischargemorphology shows that sliding discharge is formed when energized by properly adjustingmicrosecond-pulse and DC voltage.Compared to dielectric barrier discharge (DBD),the plasmaextension of sliding discharge is quasi-diffusive and stable but longer and more intensive.Resultsfrom particle image velocimetry (PIV) test indicate that plasma aerodynamic actuation by slidingdischarge can induce a ’starting vortex’ and a quasi-steady ’near-wall jet’.Body force inducedby plasma aerodynamic actuation is about the order of mN,which is stronger than that inducedby single DBD.It is inferred that microsecond-pulse sliding discharge may be more effective togenerate large-scale plasma aerodynamic actuation,which is very promising for improving aircraftaerodynamic characteristics and propulsion efficiency.
A type of electrical discharge called sliding discharge was developed to generate plasma aerodynamic actuation for flow control. A three-electrode plasma sheet actuator driven by repetitive nanosecond pulses with a negative DC component was used to generate sliding discharge, which can be called nanosecond-pulse sliding discharge. The phenomenology and behaviour of the plasma sheet actuator were investigated experimentally. Discharge morphology shows that the formation of nanosecond-pulse sliding discharge is dependent on the peak value of the repetitive nanosecond pulses and negative DC component applied on the plasma sheet actuator. Compared to dielectric barrier discharge (DBD), the extension of plasma in nanosecond-pulse sliding discharge is quasi-diffusive, stable, longer and more intensive. Test results of particle image velocimetry demonstrate that the negative DC component applied to a third electrode could significantly modify the topology of the flow induced by nanosecond-pulse DBD. Body force induced by the nanosecond-pulse sliding discharge can be approximately in the order of mN. Both the maximum velocity and the body force induced by sliding discharge increase significantly as compared to single DBD. Therefore, nanosecond-pulse sliding discharge is a preferable plasma aerodynamic actuation generation mode, which is very promising in the field of aerodynamics.
