The effect of the plasma composition on characteristics of the d.c. arc-II. Arc in argon and arc in nitrogen with water vapour

Abstract

The experimental and theoretical curves of the radial temperature distribution of the arc burning in argon, are compared with the corresponding curves in nitrogen. The theoretical curves are obtained by solving the Elenbaas-Heller energy balance equation according to Maecker. The model of the freely burning arc, under conditions usually applied in spectrochemical praxis, is considered. In accordance with theory and in comparison with the arc burning in pure nitrogen, the brilliant zone of arcs burning in argon has a steeper radial temperature distribution. If water vapour is added to an arc burning in nitrogen, the arc plasma is narrowed and the temperature increased. These experimental data can be interpreted theoretically from the solution of the energy balance equation.