abstract: The theory of non-equilibrium thermodynamics is formulated for a multi-component system consisting of two bulk phases which are separated by an interfacial region. The excesses of the mass, momentum, energy and entropy densities and their respective currents are described as singular contributions on the dividing surface to the density and current distributions. Using the Gibbs relation an expression for the excess entropy production is derived. This makes it possible to give the thermodynamic force-flux relations. The special case that the surface is planar and the transport is only in the normal direction, into and through the surface, is given special attention. The force-flux relations then give boundary conditions for the bulk fluxes at the surface.
Bedeaux