Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Physics
Multicomponent Diffusion In Two-Temperature Magnetohydrodynamics, John D. Ramshaw, C. H. Chang
Multicomponent Diffusion In Two-Temperature Magnetohydrodynamics, John D. Ramshaw, C. H. Chang
Physics Faculty Publications and Presentations
A recent hydrodynamic theory of multicomponent diffusion in multitemperature gas mixtures [J. D. Ramshaw, J. Non-Equilib. Thermodyn. 18, 121 (1993)] is generalized to include the velocity-dependent Lorentz force on charged species in a magnetic field B. This generalization is used to extend a previous treatment of ambipolar diffusion in two-temperature multicomponent plasmas [J. D. Ramshaw and C. H. Chang, Plasma Chem. Plasma Process. 13, 489 (1993)] to situations in which B and the electrical current density are nonzero. General expressions are thereby derived for the species diffusion fluxes, including thermal diffusion, in both single- and two-temperature multicomponent magnetohydrodynamics (MHD). It …
Self-Consistent Effective Binary Diffusion In Multicomponent Gas Mixtures, John D. Ramshaw
Self-Consistent Effective Binary Diffusion In Multicomponent Gas Mixtures, John D. Ramshaw
Physics Faculty Publications and Presentations
The correct treatment of diffusion in multicomponent gas mixtures requires solution of a linear system of equations for the diffusive mass fluxes relative to the mass-averaged velocity of the mixture. Effective binary diffusion approximations are often used to avoid solving this system. These approximations are generally internally inconsistent in the sense that the approximate diffusion fluxes do not properly sum to zero. The origin of this inconsistency is identified, and a general procedure for removing it is presented. This procedure applies equally to concentration, forced, pressure, and thermal diffusion, either separately or in combination. It is used to obtain a …