Home Books eBooks Journals References & Proceedings Authors, Editors, Reviewers A-Z Product Index Awards
Progress in Plasma Processing of Materials, 1999

ISBN:
1-56700-126-2 (Print)

TWO-TEMPERATURE PLASMA COMPOSITION IN SF6 PLASMA : A KINETIC MODEL

J. B. Belhaouari
Centre de Physique des Plasmas et de leurs Applications de Toulouse - ESA 5002 Université Paul Sabatier - 118 route de Narbonne - F31062 Toulouse Cedex 4 - France

R. Girard
Centre de Physique des Plasmas et de leurs Applications de Toulouse - ESA 5002 Université Paul Sabatier - 118 route de Narbonne - F31062 Toulouse Cedex 4 - France

J. J. Gonzalez
Laboratoire Plasma et Conversion d'Energie, UMR UPS-INP-CNRS5213, Université Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse cedex 9, France

Alain Gleizes
Centre de Physique des Plasmas et de leurs Applications de Toulouse (CPAT) UMR n° 5002 − Université Paul Sabatier, 118 Route de Narbonne F31062 Toulouse Cedex 4 - France

Abstract

In order to simulate departures from thermodynamic equilibrium occurring in a lot of situations like circuit breaker near current zero or plasma jets, we have developed a two-temperature plasma composition based on a kinetic model of SF6 plasma. This model takes into account the radiative and collisional mechanisms responsible for the creation and disappearance of atoms and molecules through 19 species linked by sixty-six chemical reactions. The direct reaction rates, which are function of the heavy particles temperature, proceed from literature, whereas the reverse rates, which are function of electronic temperature Te, and heavy particle temperature Th, were computed by micro-reversibility using the Saha law and are function of the parameter θ = Te/Th. A comparison is made on the results obtained with the Saha law given by Potapov and those calculated using the law given by Van de Sanden. The plasma composition is compared with the equilibrium composition obtained by classical laws of dissociation and ionisation. The difficulty on the choice of Tex is pointed out, and several diatomic and atomic species concentrations present big changes on their evolution, following the choice of Tex.