Development Of Rotating Dielectric Barrier Discharge Actuator And Study On Its Discharge Characteristics

Dielectric barrier discharge has great application prospects in aerospace,material surface modification,biomedicine and other fields,but it is still difficult to generate large-area uniform plasma in atmospheric air.Research shows that optimization of the structural parameters of the actuator is an important way to improve the characteristics of the discharge plasma.Based on the self-developed rotating dielectric barrier discharge actuator,this paper studies the influence of the electrode rotation speed on the discharge characteristics,combined with the discharge image and electrical parameters,discusses the process mechanism of power discharge in the rotating state.According to the proposed gray-level superposition method of multiple micro-discharge channels under long exposure time,gray-level mean value,standard deviation,the skewness and kurtosis of the gray-level intensity curve during electrode rotation speed changes are studied.The results show that with the increase of electrode rotation speed,the intensity of the discharge gray scale decreases and the uniformity of the micro-discharge channels distribution increases.Analysis of the texture characteristics of the micro-discharge channels found that with the increase in electrode rotation speed,the area of the discharge area increased,and the number of spots in the micro-discharge channels decreased.The discharge image showed the effect of“stretching” along the electrode tangential direction and “compressing” in the radial direction.Research on the displacement current,conduction current and power characteristics of the rotating dielectric barrier discharge actuator at different electrode rotation speeds shows that the magnitude of the displacement current is independent of electrode rotation speed.When the electrode rotation speed increases,the number of conduction current pulse clusters increases,the effective value of the current increases,and the power consumption also increases.The matching frequency of the power supply and the actuator structure is 9 k Hz,the power consumption is the lowest at this frequency,the current effective value is the smallest,and the number of pulse clusters is the smallest.Three possible theoretical mechanisms are proposed for the phenomenon of "stretching" of micro-discharge channel spots and the change of the conduction current pulse clusters in the discharge image.First,the position of the charge accumulation area of the dielectric layer changes during the rotation process,which changes the direction of the micro-discharge forming channel,that is,the micro-discharge channel is stretched.Second,considering the movement of the charge accumulation area during the rotation process,the number of seed electrons on the path increases,resulting in an increase in the number of discharge channels.Third,considering the airflow in the electrode plate air gap,the charge distribution on the surface of the dielectric layer changes,and the number of micro-discharge channels increases,resulting in an increase in the uniformity of the micro-discharge channel distribution.