Experimental Determination of the Thermal Conductivity of Atmospheric Argon Plasma

The radial temperature distribution within a cylindrically symmetric argon plasma column was determined by spectroscopic analysis for arc currents of 30 to 60 A. Temperatures obtained from absolute line and absolute continuum radiation were found to be in excellent agreement. An empirical expression, based on the Kramers-Unsöld theoretical model, was obtained for the radiated power, as a function of temperature. Using the measured temperature profiles, the calculated radiated power, and an analytical expression for the electrical conductivity, the thermal conductivity of argon was determined for the temperature range of 8500 to 12 000°K. The data were in good agreement with theoretically predicted results.