摘要：In the present work,a principle of equipartition of entransy dissipation(EoED) for heat exchanger design is established,which says that for a heat exchanger design with given heat duty and heat transfer area,the total entransy dissipation rate reaches the minimum when the local entransy dissipation rate is uniformly distributed along the heat *** the heat transfer coefficient is unfixed,the total entransy dissipation obtained by the EoED principle is less than that obtained by the principle of equipartition of temperature difference(EoTD).Furthermore,the exchanger effectiveness obtained by the EoED principle is larger than that obtained by the EoTD *** the heat transfer coefficient is fixed,the EoED principle is equivalent to the EoTD *** show that the equipartition of entropy production(EoEP) and EoED principles give rise to difference in entropy generation and entransy dissipation for a heat exchanger optimization *** discrepancies are caused by distinct features of entropy production minimization and entransy dissipation minimization principles,the former is to optimize the design of heat exchanger by making the lost available work minimum,while the latter is not involved with heat-work *** is found that the entropy generation number is not suitable for evaluating heat exchanger performance,since it directly depends on the inlet and outlet temperatures of working *** the contrary,the entransy dissipation number is not directly related to the inlet and outlet temperatures of working ***,the entransy dissipation number is more suitable for serving as a criterion to evaluate heat exchanger performance.

摘要：目的:研究余热回收中的新型烧结矿立式冷却装置填充床的阻力特性,揭示烧结矿填充床宏观特性参数和空隙流动状态,提出适用于烧结矿的阻力特性公式。创新点:1.采用实验方法,获取全面的复杂异形烧结矿颗粒宏观特性数据;2.通过实验测量,提出适用于烧结矿填充床的修正型Ergun阻力方程。方法:1.采用多种实验方法,测量烧结矿的颗粒粒度、球形度和堆积空隙率等宏观特性参数;2.通过阻力实验数据分析,得到烧结矿填充床的宏观特性参数和堆积空隙流动状态;3.通过实验数据拟合,提出适用于烧结矿的阻力特性公式。结论:1.表观流速为0.4?2.4 m/s时烧结矿填充床堆积空隙流动状态由层流过渡到湍流;***方程的不规则异形颗粒的阻力预测值比实验值偏低约40%;3.提出的修正型Ergun预测公式能够预测颗粒雷诺数500至12 000的烧结矿填充床阻力,预测误差在10%以内。

摘要：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.

摘要：In the process of the design of heat exchangers,it is difficult to establish the factors governing the optimal points of the design objective functions due to the contradictions and uncertainties of the design *** variation of fluid properties is one of the main factors causing this type of *** design methods have not completely solved these *** the present work,based on the logarithmic mean temperature difference,a new heat exchanger design method(called the segmented design method) is proposed which takes into account the variation of fluid properties with respect to the *** this method,the whole heat exchanger is first divided into several *** by applying the principle of the conservation of energy and taking into account the initial conditions as well as the connecting conditions of the adjacent segments,the inlet and outlet temperatures of each segment are ***,the application of the logarithmic mean temperature difference method on each segment defines the heat transfer area.

摘要：In this paper,by taking the water-water balanced counterflow heat exchanger as an example,the entransy dissipation theory is applied to optimizing the design of heat *** certain conditions,the optimal duct aspect ratio is determined *** the heat transfer area or the duct volume is fixed,analytical expressions of the optimal mass velocity and the minimal entransy dissipation rate are *** results show that to reduce the irreversible dissipation in heat exchangers,the heat exchange area should be enlarged as much as possible,while the mass velocity should be reduced as low as possible.

摘要：Under given heat duty and heat transfer area conditions, the equipartition of the entransy dissipation (EoED) principle, the equipartition of the temperature difference (EoTD) principle, and the equipartition of the heat flux (EoHF) principle are applied to the optimization design of a heat exchanger with a variable heat transfer coefficient. The results show that the difference between the results obtained using the EoED and EoTD principles is very small, far smaller than that between the results obtained using the EoED and EoHF principles. The correct entransy dissipation minimization principle is chosen to optimize the parameters in the hot and cold fluids in a two-fluid heat exchanger, under given heat duty and heat transfer area conditions. The results indicate that the proper choice of the two alternative fluids has an important role in the successful application of the entransy dissipation minimization principle. The fluid that could improve the total heat transfer coefficient should be chosen, or the fluid that makes the temperature profiles of the hot and cold fluids parallel and decreases the temperature difference between the hot and cold fluids after optimization simultaneously, could be the proper one.

摘要：The Alpha Magnetic Spectrometer(AMS) is an instrument for the international scientific experiment,composed of six detectors and 650 *** objective of AMS experiment is to search for dark matter and anti-matter in *** this paper,the thermal control system for AMS cryocoolers is designed,analyzed and experimentally *** loop heat pipes(LHPs) as the main heat dissipation component,the thermal control system has sufficient heat dissipation capability to prevent the cryocoolers from over temperature(+40℃) in hot environment,meanwhile to ensure temperatures of the cryocoolers higher than their lower limit(-20℃) in cold *** results show that the thermal control system for AMS cryocoolers functions stably satisfying design specification.

摘要：Thermoelectric effect is the most efficient way to convert electric energy directly from the temperature gradient. Thermoelectric effect-based power generation, cooling and heating devices are solid-stated, environmentally friendly, reliable, long-lived, easily maintainable, and easy to achieve miniaturization and integration. So they have unparalleled advantages in the aerospace, vehicle industry, waste heat recovery, electronic cooling, etc. This paper reviews the progress in thermodynamic analyses and optimizations for single- and multiple-element, single- and multiple-stage, and combined thermoelectric generators, thermoelectric refrigerators and thermoelectric heat pumps, especially in the aspects of non-equilibrium thermodynamics and finite time thermodynamics. It also discusses the developing trends of thermoelectric devices, such as the heat sources of thermoelectric generators, multi-stage thermoelectric devices, combined thermoelectric devices, and heat transfer enhancement of thermoelectric devices.

摘要：This review paper summarizes constructal design progress performed by the authors for eight types of heat sinks with ten performance indexes being taken as the optimization objectives,respectively,by combining the methods of theoretical analysis and numerical *** eight types of heat sinks are uniform height rectangular fin heat sink,non-uniform height rectangular fin heat sink,inline cylindrical pin-fin heat sink(ICPHS),plate single-row pin fin heat sink(PSRPHS),plate inline pin fin heat sink(PIPHS),plate staggered pin fin heat sink(PSPHS),single-layered microchannel heat sink(SLMCHS)with rectangular cross sections and double-layered microchannel heat sink(DLMCHS)with rectangular cross sections,*** the ten performance indexes are heat transfer rate maximization,maximum thermal resistance minimization,minimization of equivalent thermal resistance which is defined based on the entransy dissipation rate(equivalent thermal resistance for short),field synergy number maximization,entropy generation rate minimization,operation cost minimization,thermo-economic function value minimization,pressure drop minimization,enhanced heat transfer factor maximization and efficiency evaluation criterion number maximization,*** optimal constructs of the eight types of heat sinks with different constraints and based on the different optimization objectives are compared with each *** results indicated that the optimal constructs mostly are different based on different optimization objectives under the same boundary *** optimization objective should be suitable chosen based on the focus when the constructal design for one heat sink is *** results obtained herein have some important theoretical significances and application values,and can provide scientific bases and theoretical guidelines for the thermal design of real heat sinks and their applications.

摘要：Based on construtal theory, a nonuniform heat generation problem in a rectangular body is investigated in this paper. Entransy dissipation rate(EDR) is taken as the optimization objective. The optimal body shapes with constant and variable widths of the high conductivity channel(HCC) are derived. For the rectangular first order assembly(RFOA) with constant cross-section HCC, the shape of the RFOA and width ratio of the HCCs are optimized, and the double minimum EDR is obtained. The heat transfer performance of the RFOA becomes worse when the nonuniform coefficient increases. For the RFOA with variable cross-section HCC, the EDR of the RFOA can be minimized for four times. Compared the optimal construct based on minimum EDR of the RFOA with that based on minimum maximum temperature difference, the shape of the former optimal construct is tubbier, and the average temperature difference is lower. In the practical design of electronic devices, when the thermal safety is ensured, the constructal design scheme of the former optimal construct can be adopted to improve the global heat transfer performance of an electronic device.