Thermal Effects in Rarefied Binary Gas Mixtures

Abstract

Expressions are derived for the radiometer force and the thermomolecular pressure difference (thermal transpiration) in a binary gas mixture as a function of pressure from the free‐molecule to the continuum regime. The pressure dependence of the effective thermal diffusion factor is also obtained, including the effect of the simultaneously occurring thermomolecular pressure difference. Inelastic collisions are neglected. Qualitatively new features arise for mixtures that are not present for single gases.