A Design Study on a 30-KW Inductively Coupled Thermal Plasma Torch for Material Processing

Summary form only given. A 30-kW inductively coupled thermal plasma torch is designed and fabricated based on the geometrical and operating parameters derived from a numerical analysis. The optimal values of various torch design variables such as the inner radius of a confinement tube, the number of coil turns and the interval between coil turns are determined by a parametric study for finding the flow and temperature configurations of the thermal plasma flame desirable for material processing. Basic discharge experiments under the various operating conditions are carried out for the performance tests of this RF torch fabricated. The minimum power for sustaining a stable plasma and the thermal efficiency of the torch are found from the discharge experiments. In order to examine the induction thermal plasma characteristics and confirm the validity of the present design approach, the temperature and velocity fields of pure argon thermal plasma are measured at the torch exit by an enthalpy probe method and the measured data are compared with the calculated results used for the torch design