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The Poiseuille and thermal transpiration flows of a rarefied gas between two parallel plates are investigated on the basis of the linearized Boltzmann equation for hard-sphere molecules and diffuse reflection boundary condition. The velocity distribution functions of the gas molecules as well as the gas velocity and heat flow profiles and mass fluxes are obtained for the whole range of the Knudsen number with good accuracy by the numerical method recently developed by the authors. [ABSTRACT FROM AUTHOR]

Shear flow and thermal creep flow (flow induced by the temperature gradient along the boundary wall) of a rarefied gas over a plane wall are considered on the basis of the linearized Boltzmann equation for hard-sphere molecules and diffuse reflection boundary condition. These fundamental rarefied gas dynamic problems, typical half-space boundary-value problems of the linearized Boltzmann equation, are analyzed numerically by the finite difference method developed recently by the authors, and the velocity distribution functions, as well as the macroscopic variables, are obtained with good accuracy. From the results, the shear and thermal creep slip coefficients and their associated Knudsen layers of a slightly rarefied gas flow past a body are derived. The results for the slip coefficients and Knudsen layers are compared with experimental data and various results by the Boltzmann--Krook--Welander (BKW) equation, the modified BKW equation, and a direct simulation method. [ABSTRACT FROM AUTHOR]

The behavior of a semi-infinite expanse of a gas bounded by its plane condensed phase, where evaporation or condensation is taking place, is considered on the basis of the linearized Boltzmann equation for hard-sphere molecules. The half-space boundary-value problem of the linearized Boltzmann equation for hard-sphere molecules is solved numerically by the finite difference method introduced in the temperature jump problem by the authors. The local behavior of the gas (the velocity distribution function of gas molecules, the density and temperature of the gas, etc.) as well as the relations among the macroscopic variables on the condensed phase and at infinity is obtained. [ABSTRACT FROM AUTHOR]

A semi-infinite expanse of a rarefied gas over a plane wall where there is a constant heat flow normal to the wall from infinity is considered. The behavior of the gas is analyzed numerically by a finite difference method on the basis of the standard linearized Boltzmann equation for hard-sphere molecules with diffuse reflection at the wall. From the result the temperature jump coefficient and its associated Knudsen layer of a slightly rarefied gas flow around a body are derived. [ABSTRACT FROM AUTHOR]