Simpler Formulae for the Kihara-Mason Second Approximation to the Thermal Diffusion Factor of Binary Gas Mixtures

Abstract

Simpler formulae have been derived for the second approximation to the thermal diffusion factor of a binary gas mixture starting from the rigorous expression given by Mason on the extended Kihara approximation scheme. These formulae have been further specialised for the particular cases when either of the two components is in trace. The new formulae are considerably simpler than the corresponding rigorous expressions and are therefore preferable for numerical computations. The accuracies of these formulae are demonstrated by performing numerical calculations for the systems Ar-Xe and He-Xe both as a function of temperature and composition