Entropy of Irreversible Processes Across a Boundary

Abstract

A novel method for determining the entropy associated with irreversible processes has been provided, differing from the conventional theory of irreversible thermodynamics. It permits the direct relation of heat and work transfers in irreversible processes to those in reversible changes, in terms of measurable properties. The same technique is applied to the construction of thermodynamic state functions that are no longer limited to reversible phenomena. The results are then used to construct line integrals for the contribution of irreversible processes to the entropy associated with the flow of heat, work, and matter across a junction. Specific examples are provided to illustrate the procedure; they relate to changes of temperature and volume and to cycling of systems interacting with a reservoir via a thin barrier.