论文和技术资料

Abstract Microstructure-enhanced discharges are critical for achieving higher plasma electron density and energy, offering significant potential in advanced plasma applications. A two-dimensional fluid model of pulsed dielectric barrier discharge was developed in atmospheric helium with a dielectric microhole. Two distinct high-electron-density regions, the T-region and L region, were identified, driven, respectively, by transverse and longitudinal electric fields as the ionization wave traversed the microhole. The axisymmetric T-region is approached and squeezed as the radius decreases, in which the discharge intensity and electron density are enhanced. Based on the electron reaction source item, a virtual electrode is proposed in the dielectric microhole, which segregates the T- and L-regions. The width of the virtual electrode decreases with the microhole radius, and the virtual electrode extinguishes with the discharge ignition in the lower chamber and the formation of ionization wave in the dielectric microhole. These findings offer insights into plasma behavior in microstructures for advanced applications. Results 1.The microhole radius modulates discharge characteristics via transverse/longitudinal electric fields, affecting current density and electron dynamics. 2.The T-region generated by the transverse electric field,the L-region generated by the longitudinal electric field.the high electron density range of region T is also compressed with reducing radius,eventually the two T-regions are compressed into one. 3.The increase in electron density amplitude is due to the enhanced discharge in the T-region, which is influenced by the microhole radius 4.The electron dissipation in dielectric microhole proposes a virtual electrode in the discharge, as shown in Fig. 3, where the red dashed line indicates the location of the virtual electrode. In conclusion, the discharge characteristics and dynamics of ionization wave in discharge penetrated through the dielectric microhole with different radii is investigated by a numerical simulation. It shows that the smaller the microhole radius, the stronger the transverse electric field and the glow discharge in the dielectric microhole. Two kinds of high electron density regions, T- and L-regions, are observed in the discharge space. After the radius is reduced, the two axisymmetric T-regions approach and squeeze each other, leading to an increase in electron density. The discharge in the L-region is generated below a virtual electrode in the dielectric microhole, which is independent of the discharge in the T-region. The width of the virtual electrode decreases due to the decrease in the microhole radius.