Flux-based modeling of heat and mass transfer in multicomponent systems

In the present work, macroscopic governing equations heat and mass transfer for a general multicomponent system are derived via systematic nonequilibrium thermodynamics framework. contrast to previous approaches, relative (with respect average velocity) component fluxes (relative species momenta) flux treated explicitly, in complete analogy with momentum flux. The framework followed here, addition allowing description of relaxation phenomena transfer, establishes fullest between all transport processes, momentum, heat, toward which R. B. Bird contributed so much his work. inclusion flux-based as an additional variable allows well mixed (Soret Dufour) effects, coupling transfer. resulting models Galilean invariant, thereby resolving conundrum field, always second law thermodynamics, appropriate selection parameters. dynamic reduce traditional limit when effects negligible fully consistent established from application kinetic theory dilute gases. As added benefit, particular example case hyperbolic diffusion we illustrate proposed method allow use powerful numerical solvers normally not available solving more generally.