Simulation of the Processes of Formation and Dissociation of Neutral Particles in Air Plasma: Vibrational Kinetics of Ground States of Molecules

Abstract

The results are given of the calculations of populations of vibrational levels of N2(X 1·+ 8 ), О2(X 3·- 8 ), and NO(X 2Π) molecules in an air plasma whose parameters correspond to the positive column of a DC discharge at pressures of 30–300 Pa and currents of 20–110 mA. Different processes are analyzed that form the distribution of molecules over levels, including the electron impact, V–Vand V–T exchange, chemical reactions, and heterogeneous deactivation. The calculation results for N2(X 1·+ 8 ) are compared with experiment. It is found that the values of the effective vibrational temperature characterizing the populations of N2(X 1·+ 8 ) are close to the values realized in a nitrogen plasma, and the difference of the vibrational temperatures of О2(X 3·- 8 ) and NO(X 2Π) from the gas temperatures is not significant, which is due to high frequencies of V–T relaxation of vibrational states of these molecules in collisions with О(3 P) atoms.