Dynamics of Electric and Gas Dynamic Characteristics of a Spark Discharge in Subcentimeter Gap with an External RLC-Circuit

Abstract

Dynamics of the streamer development, subsequent closure of the streamer on the electrodes, and formation of a spark channel at the initial temperature 300 K and the pressure 150 Torr in an RLC circuit are studied numerically. The algorithm is based on the drift-diffusion model of the electric discharge in a gas and Euler’s system of equations for describing the ideal gas dynamics. The external part of the electric circuit is taken into account by solving the system of ordinary differential equations in the case of the time dependences of the anode potential, the capacitor voltage, and the electric current. The discharge is initiated by a 0.1 nF capacitor initially charged to a voltage of 25 kV, which discharges through a 0.5 μH inductor, a 100 Ω resistor, and a gas-discharge gap. The dynamics of the electron number density (before and after closure of the interelectrode gap by the streamer) is considered and its relationship with the electric field strength and the electric current density is studied. The pressure, density, and temperature fields during the heat input stage of the spark channel are also studied.