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OPTIMAL PERFORMANCE OF THERMOELECTRIC REFRIGERATION SYSTEM USING entropy generation minimization METHOD

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Transactions of Nanjing University of Aeronautics and Astronautics 2005年第4期22卷 339-343页

作者：曹业玲夏文庆余莉南京航空航天大学航空宇航学院

With the entropy generation minimization （EGM） method, the thermodynamical performance optimization in a thermoelectric refrigeration system is studied. The optimization is affected by the irreversibility of heat transfer caused by finite temperature differences, the heat leak between external heat reservoirs and the internal dissipation of working fluids. EGM is taken as an objective function for the optimization. The objective function and design parameters are obtained. Optimal performance curves are presented by thermal and electronic parameters. Effects of these parameters on general and optimal performances are investigated. Results are helpful in determining optimal design conditions in real thermoelectric refrigeration systems.

关键词： thermoelectric refrigeration system entropy generation minimization finite-time thermodynamics

Analyses of thermodynamic performance for the endoreversible Otto cycle with the concepts of entropy generation and entransy

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Science China(Technological Sciences) 2017年第5期60卷 692-700页

作者： WU YanQiu College of Mathematics & Statistics Chongqing Three Gorges University Chongqing 404100 China

In this paper, the endoreversible Otto cycle is analyzed with the entropy generation minimization and the entransy theory. The output power and the heat-work conversion efficiency are taken as the optimization objectives, and the relationships of the output power, the heat-work conversion efficiency, the entropy generation rate, the entropy generation numbers, the entransy loss rate, the entransy loss coefficient, the entransy dissipation rate and the entransy variation rate associated with work are discussed. The applicability of the entropy generation minimization and the entransy theory to the analyses is also analyzed. It is found that smaller entropy generation rate does not always lead to larger output power, while smaller entropy generation numbers do not always lead to larger heat-work conversion efficiency, either. In our calculations, both larger entransy loss rate and larger entransy variation rate associated with work correspond to larger output power, while larger entransy loss coefficient results in larger heat-work conversion efficiency. It is also found that the concept of entransy dissipation is not always suitable for the analyses because it was developed for heat transfer.

关键词： entropy generation minimization entransy finite time thermodynamics endoreversible Otto cycle applied mathematics

Optimization Design of the Grate Cooler Based on the Power Flow Method and Genetic Algorithms

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Journal of Thermal Science 2020年第6期29卷 1617-1626页

作者： MA Xiaoteng CAO Qun CUI Zheng Institute of Thermal Science and Technology Shandong UniversityJi'an 250061China

As an important process during the cement production,grate cooler plays significance roles on clinker cooling and waste heat *** this paper,we measured experimentally the heat balance of the grate cooler,which provided initial operating parameters for ***,the grate cooler was simplified into a series-connected heat exchanger network by power flow *** the equivalent thermal resistance network provided the global constraints by Kirchhoff’s *** this basis,with the objectives of the minimum entropy generation numbers caused by heat transfer and viscous dissipation,solving a multi-objective optimization model achieved the Pareto Front by genetic *** selecting the scheme of the lowest fan power consumption obtained the optimal operating parameters of the grate *** results showed that the total mass flow of the optimized scheme did not change significantly compared with the original scheme,but the fan power consumption was 25.44%lower,and the heat recovery efficiency was 88.43%,which was improved by 11.35%.Furthermore,the analysis showed that the optimal operating parameters were affected by the local heat *** optimizing the diameter of clinker particles within the allowable industrial range,the clinker with particle diameter of 0.02 m had the optimal performance.

关键词： power flow method genetic algorithm grate cooler entropy generation minimization multi-objective optimization

entropy resistance analyses of a two-stream parallel flow heat exchanger with viscous heating

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Chinese Physics B 2013年第8期22卷 361-364页

作者：程雪涛梁新刚 Key Laboratory for Thermal Science and Power Engineering of Ministry of Education School of Aerospace Tsinghua University

Heat exchangers are widely used in industry, and analyses and optimizations of the performance of heat exchangers are important topics. In this paper, we define the concept of entropy resistance based on the entropy generation analyses of a one-dimensional heat transfer process. With this concept, a two-stream parallel flow heat exchanger with viscous heating is analyzed and discussed. It is found that the minimization of entropy resistance always leads to the maximum heat transfer rate for the discussed two-stream parallel flow heat exchanger, while the minimizations of entropy generation rate, entropy generation numbers, and revised entropy generation number do not always.

关键词： entropy generation minimization heat exchanger entropy resistance analyses

A comparison of optimization theories for energy conservation in heat exchanger groups

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Science Bulletin 2011年第Z1期 449-454页

作者： CHEN Qun1,2,WU Jing3,WANG MoRan4,PAN Ning2 & GUO ZengYuan1 1 Key Laboratory for Thermal Science and Power Engineering of Ministry of Education,Department of Engineering Mechanics,Tsinghua University,Beijing 100084,China 2 Department of Biological and Agricultural Engineering,University of California,Davis CA 95616,USA 3 College of Energy and Power Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China 4 Earth and Environmental Sciences Division,Los Alamos National Laboratory,Los Alamos NM 87545,USA

In general,thermal processes can be classified into two categories: heat-work conversion processes and heat transfer processes. Correspondingly,the optimization of thermal processes has to have two different criteria:the well known entropy generation minimization method and the recently proposed entransy dissipation maximization method. This study analyzes the thermal issues in a heat exchanger group,and optimizes the unit arrangements under different constraints based on a suitable optimization crite-rion. The result indicates that the principle of minimum entropy generation rate is valid for optimizing heat exchangers in a ther-modynamic cycle with given boundary temperatures. In contrast,the entransy dissipation maximization is more suitable in heat exchanger optimizations involving only heat transfer processes. Furthermore,the entropy generation rate induced by dumping used streams into ambient surroundings has to be taken into account,except for that originating from the hot and cold-ends of heat exchangers,when using the entropy generation minimization to optimize heat exchangers undergoing a thermodynamic cycle.

关键词： heat exchangers optimization criterion entransy dissipation maximization entropy generation minimization