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

This paper presents the results of the numerical simulation of plasma flows inside the torch of the VKI inductively coupled plasma facility. 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 including eleven species. While the induced electric field inside the torch is computed by solving Helmholtz induction equation, a standard two-temperature formulation is used to account for non-equilibrium effects. In particular, the present analysis assesses the impact of different models for chemical kinetics and for vibration-chemistry-vibration coupling on the resulting plasma field. Solutions previously computed assuming LTE conditions are used as a reference for our benchmarks. Considerable differences on both the induced electric and temperature field are highlighted for the lower pressure cases.