Experiments on heat transfer to wires in a partially ionized argon plasma

The heat input rate to wires in a partially ionized atmospheric pressure argon plasma (the degree of ionization is 75% at maximum), of which temperature and stream velocity are known, was measured with an estimated accuracy of ±8%. The thermodynamic and transport properties of atmospheric pressure argon at temperatures below 20,000 °K were calculated taking into consideration the effect of ionization. It was found that the incompressible empirical equations of heat and mass transfer are available for the estimation of the heat input rate in such a high temperature case. It was also shown by means of probe measurements that the boundary layers in the case of our experiments are near the frozen state and it is probable that the temperature of electrons is higher than that of atoms or ions in the boundary layers.