有限时间传热的制冷循环制冷性能的热力学分析

对存在不可逆热损耗的内可逆制冷循环进行有限时间热力学分析。求得最佳制冷系数及有关性能与过程进行速率的关系;制冷性能与过程间的时间配置的关系;制冷性能与传热能力及源汇温度的关系;得出在给定条件下循环周期的极限。     

对卡诺制冷机极限制冷系数的研究

从经典热力学的基本理论出发,对理想可逆卡诺循环和实际不可逆卡诺循环的制冷系数进行了理论研究,证明了理想可逆卡诺循环的制冷系数是最高系数,分析了实际情况下制冷系的制约因素,为提高制冷系数提供了理论指导。     

两热源制冷机的制冷率密度优化

分析一系列高温和低温热源条件下连续流两热源制冷机的最佳制冷率密度与制冷系数间的关系，对存在制冷率极值情形求出了相应的性能界限。所讨论的制冷模型包括了以下四种情形：１）内，外部均不可逆；２）外部不可逆，内部可逆；３）外部可逆，内部不可逆；４）内外部均不可逆．假定所有不可逆性均由传热产生。制冷率密度人秋优化目标。     

磁制冷循环分析

磁制冷循环是磁制冷技术中的重要环节,为磁制冷机的高效运行提供了理论基础.本文结合磁制冷循环的理论研究,详细介绍了磁制冷基本循环和活性蓄冷器(Active Magnetic Regenerator,AMR)循环,重点分析了影响循环的不可逆因素,并对磁制冷循环的发展进行了展望.     

变温热源不可逆布雷顿制冷循环制冷率和制冷系数优化

用有限时间热力学方法分析变温热源不可逆简单布雷顿制冷循环的特性,分别以制冷率和制冷系数为优化目标,优化了循环中换热器的热导分配以及工质和热源间的热容率匹配,并采用数值计算分析了压比、换热器总热导、压缩机和膨胀机效率、工质热容率等参数对最优制冷率和制冷系数的影响特点.所得结果对工程制冷系统设计有一定的指导意义.     

不可逆空气制冷循环的制冷率和制冷系数优化

用有限时间热力学方法分析恒温热源不可逆空气制冷循环特性 ,在总热导率一定的条件下 ,研究最优制冷率、制冷系数时热导率的最优分配 ,并分析了各种参数对循环特性的影响 ,所得结果对工程制冷系统设计有一定的指导意义。     

氦制冷在空间制冷技术中的应用

介绍了几种用于空间制冷中的氦制冷技术，如^He减压蒸发制冷，^3He压缩相变制冷，亚临界液氦制冷，超流氦制冷等。分别介绍了它们的原理，关键技术及其应用实例，最后提出了开展这方面工作的建议。     

斯特林制冷机的最佳制冷系数和制冷率之间的关系

考虑全部传热不可逆性,导出了斯特林制冷机最佳制冷系数和制冷率间的关系。讨论了各因素对这种关系的影响。     

不可逆布雷顿制冷循环的有限时间热力学分析

研究定常态流恒温热源和变温热源不可逆布雷顿制冷循环的有限时间热力学性能，并讨论了工质与热源间的最佳匹配和非共沸工质循环的优化问题。所得结果对实际制冷工程有一定指导意义。     

电化学制冷研究

在论述电化学制冷原理的基础上，着重分析了影响电化学制冷效果的因素，分析讨论了测试结果，理论分析与实验研究表明，这是一种不受温度影响，在低温区域很有意义的新型制冷方法。     

引射吸收式制冷循环

提出了引射吸收式制冷循环。它可以强化吸收,而且可以扩大吸收式制冷的应用领域。分析了引射吸收式制冷循环,提出了参数选择方法,分析了影响引射式吸收制冷循环中吸收过程的因素并与喷淋吸收过程进行了比较。     

Electron Cooling and Control of Josephson Current at Sub-Kelvin Temperatures

The factors limiting cooling electrons by biased tunnel junctions have been considered. At low temperature range the deviation from equilibrium, superconductor overheating and states within the superconductor gap limit the achievable minimum temperature. Strong increase of electron–phonon coupling at higher temperature limits the temperature range of effective electron cooling to sub-Kelvin region. Control of Josephson coupling in superconductor-normal metal-superconductor weak link by electron cooling in normal electrode has been demonstrated experimentally.     

Working fluids for mechanical refrigeration - Invited paper presented at the 19th International Congress of Refrigeration, The Hague, August 1995

The phasing out of fully halogenated halocarbons becomes effective at the end of 1995 by international agreement. Under the same ozone depletion issue, the companion fluids HCFCs are suffering a similar fate, as they are considered controlled substances with a virtual phase-out by 2020, and more drastic reductions may be proposed in the near future. Some international action might also be agreed upon on refrigerants with regard to the threatened environmental emergency of anthropogenic global warming. Therefore, in choosing replacement fluids primary concern must be given to minimising the total warming impact, which, for most applications, calls for improved energy efficiency. During recent years, industry has scrutinised and proposed a number of new synthesised products as immediate drop-in or long-term replacements for fluids harmful to the environment. Together with some single-component new generation refrigerants, quite a few two-component, three-component or even four-component mixtures, both with zeotropic and azeotropic behaviour, are being considered. The main issues associated with the use of the new generation refrigerants are discussed, such as behaviour with oil; flammability; efficient use of temperature glides, fractionation and heat-transfer degradation with zeotropic mixtures. The full environmentally friendly option of resorting to natural fluids is also considered by examining some recent innovative applications as refrigerants of some hydrocarbons, ammonia, carbon dioxide, water and air.     

气动分置式斯特林制冷机的等温模型分析

涉及的气动分置式斯特林制冷机实验性能为40 W输入80 K/1 W,是上海技术物理研究所三期创新研究项目,本文采用等温模型对该制冷机的制冷性能进行理论计算,计算结果与实验值基本一致。另外,还对制冷机一些参数对理论制冷量、冷损、有效制冷量等的影响进行分析,为合理选取这些参数提供理论依据。     

脉管式气波制冷的实验研究

简介了同时利用压力能制冷的气波制冷与脉管制冷的原理,并对影响其效率的因素进行分析,并进行了管长,转速,充排比等对其效率影响的实验研究,得出了一些有益的结论,最后对脉管制冷与气波制冷的耦合进行了探讨。     

制冷压力容器中应力集中及改善措施探讨

对应力集中现象及概念进行了阐述,同时对制冷压力容器设计和制造过程中可能导致应力集中的因素进行归纳总结,并提出了具体的改善应力集中的措施,方便大家探讨。     

Conditionnements thermiques par fluide intermédiaire et accumulation d'énergie latenteThermal conditioning through intermediary fluid and latent power storage

As a result of direct automation of the industrial refrigerating plants the efficiency is generally reduced by: (1) not limiting the peaks of refrigeration demand; (2) not profiting by the permissible temperature variations of the stored goods; (3) allowing unstable cycles of production and distribution. From this ascertainment the authors investigate the advantages of the different forms of storing thermal energy.The conventional thermal energy storage methods are compared such as: (1) the most popular sensible heat storage by means of water or chilled water tank: (2) the storage below freezing by means of liquid solutions (salt, alcohol, glycerol, glycol…); (3) the ice accumulation systems; (4) the eutectic-plate systems. Moreover, temperature fluctuations of the stored goods in a cold store are contemplated as a posible method of storing sensible heat, if moderate (4K for frozen and 2K for fresh goods).The above-mentioned methods, using either sensible or latent heat, are compared in terms of: utilization temperature, accumulation temperature range, and storage capacity per unit mass and unit volume. Loading and unloading rates of the storage device are also significant characteristics.The development of new storage methods are then investigated mainly in respect of energy savings in the field of agro-industries requiring both refrigeration and heating. (1) The accumulation of warm water, using either electric supply during low-fare periods, or heat pumps associated to heat rejection recovery of refrigerating plants, or any combination of both sources; (2) the latent heat accumulation which allows an important space saving compared to sensible heat accumulation.The most important recent improvements are mentioned: (1) physico-chemical (supercooling, non-reversibility of the change-of-phase process, crystallizing rate and heterogeneous crystallization); (2) heat exchange problems; (3) technological constraints; (4) financial amortization.As an illustration of the advantages of heat storage, the authors present a possible application for slaughter houses aiming at energy savings by means of: (1) heat recovery from refrigerant condensation for preheating of process water, with or without thermodynamical amplification (heat pump); (2) optimization of the running cycles of the compressors and adjustment of condensing and evaporating temperature levels. The example of a 10,000 t/year slaughterhouse is presented where an eutectic accumulation device is included in the glycol-water distribution system, allowing for the transfer of a 1250 kWh refrigeration capacity from peak to low level demand periods, with a reduced volume of 25 m³.As a conclusion, the authors review the main types of application of heat storage.     

太阳能制冷技术的应用与发展

太阳能制冷具有环保节能的优点，是当前制冷界的研究热点。本文综合介绍了各种太阳能制冷技术的原理和特点。以及一些当前最新的研制成果，并对太阳能制冷技术的发展和应用前景作了分析。     

应用半导体制冷的冷藏链用储藏箱性能实验研究

半导体制冷片因其体积小、制冷速度快的优点在冷藏链运输领域具有很强的应用潜力。为测试半导体制冷箱的制冷效率,本文搭建了制冷储藏箱性能测试实验台,对应用两片TEC1-12706型及TEC1-12712型半导体制冷片的制冷储藏箱的工作性能进行实验研究。实验中分别在储藏箱中加入2 000 m L冰块开始实验及应用1 500 mL冰块与3 kg食材及3瓶500 mL矿泉水的组合开始实验,两次实验中同时改变热端散热方式及冷端风扇吹风方式。结果表明:对于同型号半导体制冷片,水冷方式时制冷效果更好,但持久性不强;同型号半导体制冷片冷端风扇下吹方式与侧吹方式相比气流组织更好。当容积为0. 1 m³的储藏箱面向冷藏需求时,可应用两片采取热端风冷方式的TEC1-12706型半导体制冷片,此时10 h内箱体中心温度最大约为6℃,最小约为0℃;当容积为0. 1 m³的储藏箱面向冷冻需求时,可应用两片TEC1-12712型半导体制冷片结合水冷式热端和风扇下吹式冷端,能维持3 h箱体内温度不高于0℃。