Two-temperature fluid model for high-pressure plasmas in contact with cooled electrodes

Abstract

A detailed continuum model of a weakly ionized plasma in stagnation flow against an electrically biased surface is presented. The model includes bulk fluid motion as well as electron and ion momentum and continuity equations in both general and quasineutral formulations. The inclusion of both electron and bulk energy equations allows for the determination of electron temperature and deviations from local thermodynamic equilibrium. Results for the quasineutral model demonstrate the importance of considering thermal nonequilibrium in the evaluation of plasma properties in the presheath region. The evaluation of transport properties is self-consistent with properties for the charged species depending on the calculated electric field and neutral number density. In addition to investigating thermal boundary layer and fluid flow effects, a finite electron-ion recombination rate at the electrode surface is employed and the consequences of varying this boundary condition are explored.