Optimal design of inductively coupled plasma torch using parametric study and design sensitivity analysis

A parametric study and a design sensitivity analysis have been carried out to find the optimal design conditions and thermal plasma configurations of an Inductively Coupled Plasma (ICP) torch. Firstly, the parametric study is conducted with the following criteria on thermal plasma properties; i) sufficiently high temperature (> 8000 K), ii) a large volume of hot temperature, and iii) no recirculating flow near the torch inlet. Next, the sensitivity of plasma temperature distributions is derived from the results of parametric study by estimating the optimal ranges of parameters and giving the initial guessing values for the sensitivity analysis. The derived sensitivity of plasma temperature distributions is analyzed using the gradient method for the thermal plasma configurations to produce the broader hot region and more uniform temperature distributions, Finally, these two results are compared, and the optimum design values for ICP torches of 15 kW usable for material processing are presented.