Numerical parametric investigation on the temperature distribution in Ar/O2 induction thermal plasmas with Ti powder injection: Inclusion of particle evaporation

Abstract

Thermal interaction between titanium feedstock powder and the thermal plasma is calculated using the developed numerical model for an inductively coupled thermal plasma (ICTP) with particle injection. The interaction between titanium powder and thermal plasmas is very important for the stable establishment of the ICTP and effective heating and evaporation of the injected particles, for example, for particle synthesis. The injected particles are heated by the thermal plasma and they melt and evaporate, contaminating the plasma and thus affecting its properties. The developed numerical model solves the mass, momentum, and energy conservation equations of thermal plasmas as well as the mass transport equation for the evaporated materials. In addition, particle motions are derived by solving the Lagrange equation of motion. The temperature distribution inside the particles and the phase transition from solid, through liquid, to gas of the particles are also taken into account. Finally, a parametric study is conducted to show the influence of the important physical parameters such as input power, sheath gas flow rate, and Ti powder feed rate. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.