Discharge properties of preformed air plasma channels

Summary form only given. The discharge properties of preformed air plasma channels are studied by a time-dependent kinetics model employing extensive non-equilibrium air-chemistry kinetics and nitrogen vibrational kinetics with rates calculated from the electron energy distribution function. The gas heating effects were accounted for via a thermal balance equation allowing for a channel expansion. The main plasma properties such as electron density and plasma conductivity, swarm parameters, electron, gas and vibrational temperature, ion densities, population of nitrogen and oxygen electronically excited molecular states and nitrogen vibrational distribution function were obtained as a function of the initial electron density and applied electric field. It was observed that the initial stage of the discharge is controlled by recombination; at later times the attachment takes over and becomes the dominant process in the electron dynamics leading to a fast decrease of the electron density. If ionization overcomes attachment, ionization instability is observed and breakdown ensues. The results of the model are compared with experimental results available in literature such as electron conductivity, discharge current, gas heating, and swarm parameters