Numerical study of radiative heat effects in inductively coupled plasma discharges

This study presents a numerical investigation of the impact of radiative processes in inductively coupled plasmas (ICPs) using a state-of-the-art multi-physics computational framework developed at The Center for Hypersonics and Entry Systems Studies (CHESS) at the University of Illinois at Urbana-Champaign. The physical model addresses non-local thermodynamic equilibrium (NLTE) effects in plasmas through a multi-temperature model formulation. Fluid governing equations are spatially discretized using a cell-centered finite volume method and are tightly coupled to the electromagnetic and radiative transfer equations required for modelling external fields and radiation transfer. The electromagnetic (EM) equations are numerically solved with a mixed finite-element solver capable of handling both time-dependent and frequencydomain Maxwell’s equations, while the radiation transport equation is discretized using a finite volume-based method. The problem under investigation involves the flow within the CHESSP lasmatron X facility, the country’s largest ICP plasma wind tunnel. The analysis focuses on the flow within the torch used for plasma generation. Findings from the investigation reveal that the effect of radiation transport becomes necessary for pressures exceeding 5 kPa.