title: Multicomponent gas transport coefficients: alternate formulations.
abstract: The phase rule states that a fluid element is determined locally by c+1 independent intensive variables when there are c components. In solving the Boltzmann equation for gas transport coefficients, the standard procedures involve only c independent gradients of intensive variables for the local properties (exclusive of the convective motion). This paper addresses this disparity and proposes an alternative set of gradients when solving the Boltzmann equation. The consequence is added terms in the expressions for the thermal diffusion coefficients. As well, the standard expression for the binary diffusion constant is identified as being valid only at constant total density. Irreversible thermodynamics is used as a reference base for comparing the alternate formulations.
authors.affiliation: Department of Chemistry, University of British Columbia, Vancouver, Canada V6T 1Z1.
authors.forename: R F
authors.initials: RF
authors.lastname: Snider