Chemical reactions in endoreversible thermodynamics

Abstract

Endoreversible thermodynamics is a theory for the (approximate) description of thermodynamic non-equilibrium systems, which allows us to capture the ever present irreversibilities of real processes. For instance in heat engines the dissipation due to finite heat transport capabilities, as well as the resulting limitations in the energy fluxes, can be incorporated into the theory. It has thus been very successful in closing the gap between observed and theoretically predicted efficiencies. Here an extension of the theory is provided, with which chemical reactions can be included in the formalism. This opens up a wide field of applications for endoreversible modeling and the investigation of dissipative processes, for instance in fuel cells or batteries.

On the Efficiency of Electrochemical Devices from the Perspective of Endoreversible Thermodynamics

“…The steady operation has to comply with the balance of energy and balance of entropy expressed via energy fluxes, i. e., the heat flux J q and enthalpy flux J Dh . Transformation of chemical or heat energy into nonexpansion work can be formulated by the thermodynamic property enthalpy, H, as [1,6]…”

“…The concept of endoreversible thermodynamics assumes that all irreversibilities may be treated as a transport of heat and/or mass from a source to a sink, as stated in [2,3,4,5,6] and references therein. The presented approach slightly differs from the endoreversibility concept and it is connected with the principle of minimum entropy production and with the attenuation of fluctuations of all thermodynamic quantities.…”

Dissipative Endoreversible Engine with Given Efficiency

“…Recently, it has also been extended to the the study of stochastic heat engines [32][33][34]. Since endoreversible thermodynamics is by no means limited to heat engines, it has also been used to study global wind energy production [35], chemical reactions [36][37][38], and even goods at a market [39], to name a few. The same basic ideas, in particular the optimization of processes, are also used in the context of quantum thermodynamics [40][41][42][43][44][45].…”

Entropy Generation Minimization for Reverse Water Gas Shift (RWGS) Reactors

“…FTT, also known as entropy generation minimization (EGM) [ 31 , 32 , 33 , 34 , 35 ] in engineering, can obtain the optimal performances and optimal configurations of various energy conversion devices and systems subjected to finite-time and/or finite-size, and the optimal results obtained are more powerful to guide thermal designs and optimizations of real-word devices. The wide applications of FTT in chemical reactions, heat and mass transfer processes have obtained many important theoretical achievements [ 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 ]. Månson and Andresen [ 36 ] firstly applied FTT to obtain the optimal paths of ammonia reactor with the maximum production rate as the objective function.…”

“…Chen et al [ 40 ] obtained EGM analytical solutions of the combustion chemical reactions subjected to a given fuel conversion, which obey general rate equations. Wagner and Hoffmann [ 41 , 42 ] established endoreversible models of finite-rate chemical reactions [ 41 ] and used these extensions of endoreversible thermodynamics to investigate the maximum power output of a fuel cell [ 42 ]. Some scholars had studied the optimal configurations of the heat reservoir temperature profiles of the industrial reactors in depth by using the minimum EGR as an objective function, including the sulfur dioxide oxidation reactor [ 43 ], the tubular steam reformer [ 44 , 45 ] and the sulfuric acid decomposition reactor [ 46 ].…”