Thermal non-equilibrium in a preionized argon plasma kept between two plane parallel plates in the presence of an applied electric field parallel to the surface is investigated theoretically. A multifluid theory is formulated taking into consideration the kinetics of sheath region formed near the surface. With the local transport properties accurately evaluated from kinetic theory, the system of equations is solved numerically. The influence of various parameters on thermal non-equilibrium characteristics is studied. The present study reveals substantial deviations from LTE in the regions near the wall at lower currents. Of the several modes of energy transfer mechanisms identified near the wall, the heat conduction of heavy particles is found to be the dominating one. Numerical experiments show that both electron temperature gradient and electron energy flux at the wall are negligible and consequently in all multifluid analysis it is proposed that the electron subgas may be taken as thermally insulated at the boundaries.
Transport and Structural Formation in Plasmas