Fluid-like transport variables in a kinetic collisionless plasma near a surface with ion and electron reflection

Transport variables of the positive ions and electrons in the presheath and sheath of a plasma near a wall that partially reflects ions and electrons are determined from a kinetic analysis. Because velocity distributions of the ions and electrons near the wall are highly non-Maxwell-Boltzmann distributions, accurate predictions of transport variables, such as density, fluid velocity, mean pressure, fluid-like viscous stress, and conduction, require kinetic analysis. The results find that dimensionless transport variables of ions and electrons in the presheath and sheath can be exactly expressed in terms of transcendental functions determined by dimensionless independent parameters of ion and electron reflectivities of the wall, ion-to-electron mass ratio, charge number, and electron-to-ion temperature ratio at the presheath edge. The effects of the parameters on transport variables at the wall are also obtained. The computed transport variables in the presheath and sheath show agreement with available theoretical data for a completely absorbing wall.