Experimental and numerical study of external plume Characteristics in microhollow cathode discharges

Abstract

Microhollow cathode (MHC) discharges are a class of miniature nonequilibrium high-pressure plasma discharges characterized by intense radiation and high gas temperatures. A prominent plume-like structure envelopes the region immediately outside the hollow cathode and the plume optical characteristics provide a direct indication of discharge behavior. Optical emission imaging and self-consistent numerical simulation of the discharge and in particular the plume are compared. Experimental trends of the plume size and intensity with varying discharge parameters are similar to computational results.