Modeling of non-equilibrium plasmas in an inductively coupled plasma facility

Abstract

This work presents the results of the numerical simulation of ionized gas flows inside the torch of an inductively coupled plasma facility in the von Karman Institute for Fluid Dynamics. The main purpose of this work is the parametric investigation of thermo-chemical non-equilibrium effects on the plasma jet at different operating pressures ranging from 3 to 15 kPa. The test gas is an ionized air mixture represented by eleven species. The induced electric field inside the torch is computed by solving Helmholtz induction equation. The non-equilibrium effects are modeled using a standard two-temperature formulation. In particular, the present analysis assesses the impact of different chemical kinetics models and vibration-chemistry-vibration coupling models on the resulting flow and electro-magnetic fields. Results of the present work are compared with solutions previously computed by assuming local thermodynamic equilibrium (LTE)conditions and significant differences on both the induced electric and temperature field are observed especially for the low pressure cases.