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Author Munafò, A. ♦ Alfuhaid, S. A. ♦ Panesi, M. ♦ Cambier, J. -L.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS ♦ ATOMS ♦ CHEMICAL COMPOSITION ♦ CHEMICAL STATE ♦ CONSERVATION LAWS ♦ LTE ♦ MAGNETIC FIELDS ♦ MAGNETOHYDRODYNAMICS ♦ PLASMA ♦ RADIOWAVE RADIATION ♦ SPECTRA ♦ TEMPERATURE DISTRIBUTION ♦ TIME DEPENDENCE
Abstract The objective of the present work is the development of a tightly coupled magneto-hydrodynamic model for inductively coupled radio-frequency plasmas. Non Local Thermodynamic Equilibrium (NLTE) effects are described based on a hybrid State-to-State approach. A multi-temperature formulation is used to account for thermal non-equilibrium between translation of heavy-particles and vibration of molecules. Excited electronic states of atoms are instead treated as separate pseudo-species, allowing for non-Boltzmann distributions of their populations. Free-electrons are assumed Maxwellian at their own temperature. The governing equations for the electro-magnetic field and the gas properties (e.g., chemical composition and temperatures) are written as a coupled system of time-dependent conservation laws. Steady-state solutions are obtained by means of an implicit Finite Volume method. The results obtained in both LTE and NLTE conditions over a broad spectrum of operating conditions demonstrate the robustness of the proposed coupled numerical method. The analysis of chemical composition and temperature distributions along the torch radius shows that: (i) the use of the LTE assumption may lead to an inaccurate prediction of the thermo-chemical state of the gas, and (ii) non-equilibrium phenomena play a significant role close the walls, due to the combined effects of Ohmic heating and macroscopic gradients.
ISSN 00218979
Educational Use Research
Learning Resource Type Article
Publisher Date 2015-10-07
Publisher Place United States
Journal Journal of Applied Physics
Volume Number 118
Issue Number 13


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