Gouy-Stodola theorem

The product of thermodynamic forces and fiows yields the rate of entropy production in an irreversible process. The Gouy-Stodola theorem states that the lost available energy (work) is directly proportional to the entropy production in a nonequilibrium phenomenon. Transport phenomena and chemical reactions are nonequilibrium phenomena and are irreversible processes. Thermodynamics, fiuid mechanics, heat and mass transfer, kinetics, material properties, constraints, and geometry are required to establish the relationships... 

Generally, a chemical reaction has a nonlinear relation between the rate and the driving force AIT. Chemical reactors are often designed to operate at the maximum rate of reaction. An alternative is a reactor operated with minimum useful work lost. The lost work per unit time in a chemical reactor is given by the Gouy—Stodola theorem, and is obtained by integrating the entropy production rate over the reactor volume ... 

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