Effects of anode nozzle geometry on thermal plasma characteristics generated by non-transferred torches for material processing

Summary form only given. The thermal plasma characteristics produced by the nontransferred torches with various anode nozzle geometries, such as a tubular nozzle and a stepped nozzle, operating at an atmospheric pressure are calculated and measured by a numerical simulation and an optical emission spectroscopy, respectively. On the basis of the assumption of local thermodynamic equilibrium (LTE) and optically thin plasmas, the temperature distributions of argon thermal plasmas are determined by the Abel inversion and Boltzmann plot methods for the measured intensity of Ar I lines.