Phenomenological coefficients and frames of reference for transport processes in liquids and membranes. Part 2.—Resistance and conductance coefficients in non-isothermal systems

Abstract

Phenomenological descriptions of transport processes in isotropic, non-reacting, non-isothermal systems are discussed in terms of thermal conductance and thermal resistance coefficients. It is shown that, for a non-viscous system containing n species, there is a set of 2n-1 independent thermal coefficients whether or not the system is at mechanical equilibrium. If the thermal coefficients are symmetric, then the number of independent coefficients is reduced to n. It is also shown that thermal resistance coefficients are related simply to heats of transfer, and both quantities are independent of the choice of reference velocity. If any set of thermal coefficients is symmetric, the symmetry of all other sets of thermal and isothermal coefficients is implied. The converse, however, is not necessarily true.