Progress in Plasma Processing of Materials, 2003

ISBN Print: 978-1-56700-192-1

ISBN Online: 978-1-56700-447-2

TRANSPORT COEFFICIENTS IN NON-EQUILIBRIUM ARGON-HYDROGEN THERMAL PLASMAS

DOI: 10.1615/ITPPC-2002.340
pages 269-274

Résumé

Transport coefficients in non-equilibrium argon-hydrogen thermal plasmas, where the kinetic temperature of electrons Te is different from that of heavy species Th , are calculated at atmospheric pressure from a recent theoretical approach of Rat et al. The latter consists in deriving transport properties in thermal plasmas from the solution of the Boltzmann's equation according to the Chapman-Enskog method keeping the coupling between electrons and heavy species.
Plasma composition is obtained from a non-equilibrium constant method and a stationary kinetic calculation. First, electrical and translational thermal conductivities are compared with those evaluated with the simplified theory of transport properties of Devoto and Bonnefoi. Non-negligible discrepancies occur reaching more than 30 and 40 % respectively for the electrical and electron thermal conductivities at Te = 15000 ? for θ = 2. Second, the dependence with Te of electrical and total thermal conductivities (including translational, internal and reactional contributions) and viscosity is examined as a function of the method of calculation of plasma composition and the non-equilibrium parameter θ = Te /Th . It is emphasized that non-equilibrium transport coefficients are strongly dependent on the method of plasma composition.