Observation of discharge patterns in a coaxial dielectric barrier discharge

摘要

Dielectric barrier discharge (DBD) based devices for VUV excimer radiation at high pressure involve selfextinguishingprocess due to the accumulation of charges on dielectric surfaces. The significance of the accumulatedcharges exemplified an improvement in the efficiency of such devices. We report here a coaxial DBD device usingargon gas and driven by a high repetition rate unipolar microsecond square pulses. In this paper, oscillographicstudies of filamentary modes at high pressure (300 mbar) and types of discharge patterns are presented. Non-uniformdistributions of electric field lines enhance such discharge patterns, which are visually distinguishable from restfilamentary discharges in the gas gap. In addition, electrostatic and electrodynamics simulations have been carriedout to explore the nature of discharge patterns in the coaxial cylindrical system.