Entropy generation minimization (finite time thermodynamics, or thermodynamic optimization) is the method that combines into simple models the most basic concepts of heat transfer, fluid mechanics, and thermodynamics. These simple models are used in the optimization of real (irreversible) devices and processes, subject to finite‐size and finite‐time constraints. The review traces the development and adoption of the method in several sectors of mainstream thermal engineering and science: cryogenics, heat transfer, education, storage systems, solar power plants, nuclear and fossil power plants, and refrigerators. Emphasis is placed on the fundamental and technological importance of the optimization method and its results, the pedagogical merits of the method, and the chronological development of the field.

Entropy generation minimization: The new thermodynamics of finite-size devices and finite-time processes

Abstract The historical background, research development, and the state-of-the-art of finite time thermodynamic theory and applications are reviewed from the point of view of both physics and engineering. The emphasis is on the performance optimization of thermodynamic processes and devices with finite-time and/or finite-size constraints, including heat engines, refrigerators, heat pumps, chemical reactions and some other processes, with respect to the following aspects: the study of Newton's law systems, an analysis of the effect of heat resistance and other irreversible loss models on the performance, an analysis of the effect of heat reservoir models on the performance, as well as the application for real thermodynamic processes and devices. It is pointed out that the generalized thermodynamic optimization theory is the development direction of finite thermodynamics in the future.

Finite Time Thermodynamic Optimization or Entropy Generation Minimization of Energy Systems

Optimization of thermal systems based on finite-time thermodynamics and thermoeconomics

The effect of thermal resistance, heat leakage and internal irreversibility resulting from the working fluid on the performance of a Carnot heat engine is investigated using a new cyclic model. The power output and efficiency of the heat engine are adopted as objective functions for heat engine optimization. The optimal performance of the heat engine is analysed systematically. Some significant results are obtained. For example, the maximum power output and maximum efficiency are determined. The efficiency of the heat engine at maximum power output and the power output of the heat engine at maximum efficiency are also calculated. Curves of the power output varying with the efficiency of the heat engine are obtained. These curves can indicate clearly the rational regions of efficiency and power output for an irreversible Carnot heat engine. It is pointed out that all the conclusions concerning a reversible Carnot heat engine, an endoreversible Carnot heat engine only affected by thermal resistance and an irreversible Carnot heat engine with internal irreversibility and/or heat leakage can be deduced from the results in this paper.

https://iopscience.iop.org/article/10.1088/0022-3727/27/6/011/pdf

The maximum power output and maximum efficiency of an irreversible Carnot heat engine

A new kind of power analysis is conducted on a reversible Joule-Brayton cycle. Although many performance analyses have been carried out resulting in famous efficiencies (Carnot, Curzon-Ahlborn), most do not consider the sizes of the engines. In the studies of Curzon and Ahlborn and others, researchers utilized the thermal efficiency at maximum power as an efficiency standard for practical heat engines. In this paper, instead of just maximizing power for certain cycle parameters, the power density defined as the ratio of power to the maximum specific volume in the cycle, is maximised. Therefore the effects of the engine sizes were included in the analysis. The result showed a new type of efficiency at the maximum power density which is always greater than that at the maximum power (Curzon-Ahlborn efficiency). Evaluations show that design parameters at the maximum power density lead to smaller and more efficient Joule-Brayton engines.

https://iopscience.iop.org/article/10.1088/0022-3727/28/7/005/pdf

Chih Wu

Papers

Finite-time thermodynamic analysis of a Carnot engine with internal irreversibility

Power optimization of a finite-time Carnot heat engine

Specific output power of a dry geothermal plant