Copper vapor effect on RF inductively coupled SF/sub 6/ plasmas

Abstract

Considering inductively coupled plasma (ICP) as an alternative way to study the copper (Cu) vapor effect in SF/sub 6/ circuit breaker arcs, a two-dimensional, axisymmetric model was solved, for a torch of 82-mm inner diameter, to predict the change of plasma properties: temperature, velocity, electric and magnetic fields, joule heating, and Lorentz force. For the four considered sets of thermophysical properties with 0%, 0.1%, 1%, and 10% Cu concentration (molar) ratio in SF/sub 6/, plasma properties were calculated for 130-slpm gas flow: 80-slpm SF/sub 6/ in the sheath channel and 50-slpm argon in the intermediate channel at pressure 100 and 200 torr. The radial temperature distribution as well as the Lorentz force and the joule heating broadened along the torch diameter by Cu vapor admixture. This predicted elongation of plasma for Cu vapor inclusion was confirmed experimentally determining the radial temperature distribution.