Chen Lingen, Xiao Qinghua, Feng Huijun
Institute of Thermal Science and Power Engineering, Naval University of Engineering, Wuhan 430033, China.
Military Key Laboratory for Naval Ship Power Engineering, Naval University of Engineering, Wuhan 430033, China.
Entropy (Basel). 2018 Jan 19;20(1):74. doi: 10.3390/e20010074.
Combining entransy theory with constructal theory, this mini-review paper summarizes the constructal optimization work of heat conduction, convective heat transfer, and mass transfer problems during the authors' working time in the Naval University of Engineering. The entransy dissipation extremum principle (EDEP) is applied in constructal optimizations, and this paper is divided into three parts. The first part is constructal entransy dissipation rate minimizations of heat conduction and finned cooling problems. It includes constructal optimization for a "volume-to-point" heat-conduction assembly with a tapered element, constructal optimizations for "disc-to-point" heat-conduction assemblies with the premise of an optimized last-order construct and without this premise, and constructal optimizations for four kinds of fin assemblies: T-, Y-, umbrella-, and tree-shaped fins. The second part is constructal entransy dissipation rate minimizations of cooling channel and steam generator problems. It includes constructal optimizations for heat generating volumes with tree-shaped and parallel channels, constructal optimization for heat generating volume cooled by forced convection, and constructal optimization for a steam generator. The third part is constructal entransy dissipation rate minimizations of mass transfer problems. It includes constructal optimizations for "volume-to-point" rectangular assemblies with constant and tapered channels, and constructal optimizations for "disc-to-point" assemblies with the premise of an optimized last-order construct and without this premise. The results of the three parts show that the mean heat transfer temperature differences of the heat conduction assemblies are not always decreased when their internal complexity increases. The average heat transfer rate of the steam generator obtained by entransy dissipation rate maximization is increased by 58.7% compared with that obtained by heat transfer rate maximization. Compared with the rectangular mass transfer assembly with a constant high permeability pathway (HPP), the maximum pressure drops of the element and first-order assembly with tapered HPPs are decreased by 6% and 11%, respectively. The global transfer performances of the transfer bodies are improved after optimizations, and new design guidelines derived by EDEP, which are different from the conventional optimization objectives, are provided.
本文将熵产理论与构建理论相结合，总结了作者在海军工程大学工作期间对热传导、对流换热和传质问题的构建优化工作。熵产耗散极值原理（EDEP）应用于构建优化，本文分为三个部分。第一部分是热传导和翅片冷却问题的构建熵产耗散率最小化。它包括对带有锥形单元的“体积到点”热传导组件的构建优化、在优化末级结构的前提下和没有此前提的情况下对“圆盘到点”热传导组件的构建优化，以及对四种翅片组件（T形、Y形、伞形和树形翅片）的构建优化。第二部分是冷却通道和蒸汽发生器问题的构建熵产耗散率最小化。它包括对具有树形和平行通道的发热体的构建优化、对强制对流冷却的发热体的构建优化，以及对蒸汽发生器的构建优化。第三部分是传质问题的构建熵产耗散率最小化。它包括对具有恒定和锥形通道的“体积到点”矩形组件的构建优化，以及在优化末级结构的前提下和没有此前提的情况下对“圆盘到点”组件的构建优化。这三个部分的结果表明，热传导组件的内部复杂性增加时，其平均传热温差并不总是降低。通过熵产耗散率最大化获得的蒸汽发生器的平均传热速率比通过传热速率最大化获得的提高了58.7%。与具有恒定高渗透路径（HPP）的矩形传质组件相比，具有锥形HPPs的单元和一级组件的最大压降分别降低了6%和11%。优化后传递体的整体传递性能得到改善，并提供了由EDEP推导的不同于传统优化目标的新设计准则。
