Discrete Systems in Thermal Physics and Engineering -- A Glance from Non-Equilibrium Thermodynamics

Wolfgang Muschik

doi:10.1007/s00161-021-01037-9

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arXiv · 2010.14241

Discrete Systems in Thermal Physics and Engineering -- A Glance from Non-Equilibrium Thermodynamics

Wolfgang Muschik

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Abstract

Non-equilibrium processes in Schottky systems generate by projection onto the equilibrium subspace reversible accompanying processes for which the non-equilibrium variables are functions of the equilibrium ones. The embedding theorem which guarantees the compatibility of the accompanying processes with the non-equilibrium entropy is proved. The non-equilibrium entropy is defined as a state function on the non-equilibrium state space containing the contact temperature as a non-equilibrium variable. If the entropy production does not depend on the internal energy, the contact temperature changes into the thermostatic temperature also in non-equilibrium, a fact which allows to use temperature as a primitive concept in non-equilibrium. The dissipation inequality is revisited, and an efficiency of generalized cyclic processes beyond the Carnot process is achieved.

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BibTeX RIS

Wolfgang Muschik. 2020-10-27. Discrete Systems in Thermal Physics and Engineering -- A Glance from Non-Equilibrium Thermodynamics. https://doi.org/10.1007/s00161-021-01037-9

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