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Updated: Aug 11, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Average entropy dissipation in irreversible mesoscopic processes
1Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA.
Abstract:
The Clausius inequality is rectified to obtain expressions for the entropy produced as the result of irreversible work and/or heat exchanges. These are combined with the Jarzynski equality and its generalizations to explicitly relate mean (as opposed to transient) entropy dissipation to experimental or simulation observables. The results are extended to nonisothermal processes which begin and end at nonequilibrium steady states, leading to a new exact expression and positive lower bound for the resulting average entropy dissipation. The Carnot engine emerges as a limiting case of a family of irreversible processes arising from an interface between materials at different temperatures, whose mapping onto reversible and irreversible molecular extension experiments is discussed.
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