Influence of atom-atom collisions on thermal equilibrium in argon arc discharges at atmospheric pressure

Abstract

A collisional radiative model is used to obtain the number densities of the ground level and of the excited levels of neutral argon as a function of the local ne and Te values. This model is first applied to a homogeneous and stationary medium for 5000K<Te<12000K. The local values of the density of atoms in the ground level and of the heavy particles (neutrals and ions) temperature Tg in a non-LTE discharge are determined. The C-R model is then applied to the positive column of a stationary argon arc. The ambipolar flux of electrons is evaluated and compared to the net rate of electron production.