Features of Transient Processes in DC Microdischarges in Molecular Gases: From a Glow Discharge to an Arc Discharge with a Unfree or Free Cathode Regime

Abstract

A unified self-consistent model is formulated to describe a discharge gap, electrodes, and the formation of the parameters of dc microdischarges in molecular gases at atmospheric pressure. Numerical experiments performed in the current density range from 90 to 2.5 × 106 mA/cm2 have revealed the dependence of the voltage drop on a discharge on the current density, which reproduces the formation of glow, transient from glow to arc, and arc regimes. It has been shown that a transition from the glow discharge to the arc discharge with a free and unfree cathode regime can be implemented depending on boundary conditions on the outer edges of electrodes.

Topics & Concepts