利用工业余热来驱动的喷射式制冷机

本文阐述了以喷射式制冷机为基础，以ＨＣＦＣ－１２３为工质，利用工业余热或废热不驱动的一种新型冷水机组的工作原理，系统结构以及热力计算，并与其他类型的冷水机组进行了技术经济比较，说明这种新型冷水机组是一种值得推广和进一步研究的制冷装置。     

低位余热氟利昂喷射式制冷机通过部级鉴定

重庆建筑工程学院供热通风与空调教研室低位热能制冷科研且根据国家建设部和重庆市科委下达的样机研制任务,在重庆冷冻机厂等单位的大力合作下,研制成功了我国第一台 DYFPL82—11113/2.32型低位余热氟利昂喷射式制冷机,样机1989年     

余热利用型溴化锂双效吸收式制冷机的研究

本文介绍了由上海交通大学制冷工程研究所与潍坊制冷空调设备厂联合研制开发的余热利用型溴化锂双效吸收式制冷机的流程结构特点,并运用流程模拟的方法进行了变工况特性的计算机模拟分析,还给出了一个应用实例的经济分析。     

利用永磁体的室温磁制冷机性能研究

介绍了利用1.5 T永磁体驱动,氦气作为换热流体,采用主动式磁回热器的室温磁制冷机的实验研究情况.在现有实验装置下,通过调节气体压力与循环频率,高低温端最大达到了10.7K的温差,研究结果为室温磁制冷机的设计以及进一步发展提供了参考.     

利用低温位热能驱动的喷射式制冷机制冷工质的研究

本文通过对利用低温热能来驱动的喷射式制冷机的几种制冷工质的理论分析和热力计算，找出了各种工质的最佳应用温度范围，并筛选出了比较理想的制冷工质     

脉管制冷机的性能特征

为了研究脉管制冷机的性能特征，本研究课题业已完成了多项实验。结果发现，瞬态或起动期间的冷却时间ｔｃ由脉管壁时间常数τｐｔ所控制，且基本型脉管（ＢＰＴ）制冷机的动态特性可作为一阶系统处理。在稳态运行中，已发现冷端温度ＴＬ随τＰｔ而变化，并且冷负荷ＱＬ随τｐｔ增大而单值增大。这表明，由气体从冷端至热端所泵送的热量随ｈｐｔ的下降而增大（即气体与壁之间的能量交换较小）。从而表明，脉管壁的储热或放热过程对ＢＰＴ制冷机的性能具有消极的作用。还以实验方法发现，脉管内气体的压缩／膨胀过程可以说明ＢＰＴ制冷机的性能，这些过程类似于布雷顿循环，不过介于等温和绝热过程之间。本文实验还表明，脉管制冷机在瞬态和稳态的性能主要地是由脉管壁时间常数τｐｔ，所控制。     

不可逆卡诺制冷机的最优性能

本文在内可逆卡诺制冷机模型的基础上,引进不可逆程度Ⅰ来描述传热以外的其它不可逆性,从而建立了不可逆卡诺制冷机模型,导出其基本优化公式一最佳制冷系数与制冷率间的关系。由此揭示了不可逆因素对制冷机各种优化性能的影响,并指出有限时间热力学理论时实际制冷机的重要指导意义。     

Enhanced ejector refrigeration cycles powered by low grade heat. Part 2. Design procedures

In Part 1 of this work, the conventional and compression enhanced ejector refrigeration cycles were discussed from a thermodynamic and conceptual point of view. This paper describes the development of procedures which will enable system design, optimization and control of operation. Special attention is given to the ejector design and the recommended modification of conventional system components such as the evaporator and generator. A multi-ejector system is introduced in order to expand the range in which the system may operate efficiently.     

Enhanced ejector refrigeration cycles powered by low grade heat. Part 1. Systems characterization

Conventional and improved ejector refrigeration cycles are discussed. Special emphasis is given to the adaptation of these cycles for the utilization of low grade or waste heat. A compression enhanced ejector system is suggested as a mechanically efficient way to improve the ejector cycle. It is demonstrated that a combination of mechanical and thermal energies may provide a wide range of design alternatives which should yield a competitive refrigeration system. The paper provides an over-all view of the systems by discussing their principle of operation, expected performance and design considerations.     

Performance improvement and comparison of mass recovery in CaCl2/activated carbon adsorption refrigerator and silica gel/LiCl adsorption chiller driven by low grade waste heat

One CaCl₂/activated carbon-ammonia adsorption refrigerator and one silica gel/LiCl-methanol chiller was designed and tested. The comparison of performance improvement of mass recovery process on the two adsorption systems was studied. The results show that the COP (coefficient of performance) and SCP (specific of cooling power) can be improved by 15.4% and 10.5% by mass recovery process in silica gel/LiCl-methanol chiller, while they can be improved by 53.8% and 51.5% in CaCl₂/acitvated carbon-ammonia refrigerator, because the latter has larger pressure difference between the hot and cold bed. Both the CaCl₂/acitvated carbon-ammonia refrigerator and the silica gel/LiCl-methanol chiller can provide continuous and stable cooling capacity. Under nominal working condition, the evaporator temperature, COP and SCP can reach −21 °C, 0.26 and 474 W kg⁻¹ in CaCl₂/activated carbon-ammonia refrigerator, and they are 15 °C, 0.41 and 244 W kg⁻¹ in the silica gel/LiCl-methanol chiller.     

A theoretical and experimental study of a small-scale steam jet refrigerator

The paper provides the results of a theoretical and experimental study of a steam jet refrigerator. A small-capacity steam jet refrigerator has been tested with boiler temperatures in the range 120–140°C. The experimental data were found to be within 85% of the theoretical values. The experiments showed that choking of the secondary flow in the mixing chamber of the ejector plays an important role in the system performance. Maximum COP was obtained when the ejector was operated at its critical flow condition. Off-design performance characteristics of the system are provided.     

Optimal design of an absorption chilled water storage air conditioning system driven by waste heat

In order to meet both economic and energy requirements, this study has proposed an optimal design to minimize the sum of the initial and operation energy costs for a 1200 refrigeration ton chiller and 12 water storage tanks in an absorption chilled water storage air conditioning system. Various power consumption calculation methods for the main devices are included to predict the performance of this equipment under different operating conditions. In addition, the performance curves of the water storage tank under the storage and discharge modes are calculated using Fluent software. The article uses five control strategies for a cooling tower along with three hot water inlet temperatures of a generator to simulate the optimal design of a system. The results show that the least power (10,336 kWh) is consumed when the cooling tower’s outlet temperature is 32°C and the generator’s inlet hot water temperature is 105°C.     

Performance optimization for two-stage thermoelectric refrigerator system driven by two-stage thermoelectric generator

A new configuration of combined thermoelectric device, two-stage thermoelectric refrigerator driven by two-stage thermoelectric generator, is proposed in this paper. The thermodynamic model of the combined device is built by using non-equilibrium thermodynamic theory. The analytical formulae for the stable working electrical current, the cooling load versus the working electrical current, and the coefficient of performance (COP) versus the working electrical current of the combined device are derived. For the fixed total number of thermoelectric elements of the combined device, the allocations of the thermoelectric element pairs among the two thermoelectric generators and the two thermoelectric refrigerators are optimized for maximum cooling load and COP, respectively. The influences of the heat source temperature of the two-stage thermoelectric generator and the heat source (cooling space) temperature of the two-stage thermoelectric refrigerator on the optimal performance of the combined thermoelectric device are analyzed by detailed numerical examples.     

低环境温度空气源热泵的设计及其在我国寒冷地区的应用

基于低环境温度空气源热泵在寒冷地区应用的特点,针对产品设计及工程应用中遇到的若干问题,分别对融霜方式、系统控制方式、水/制冷剂换热器的选择、辅助电加热和末端方式的选择等进行分析和讨论,通过计算得到低环境温度空气源热泵作为北方寒冷地区单户采暖热源的一次能耗为35.9 kW·h/（m2·a）,与分户燃气炉相当,低于除大、中规模热电联产外其他热源形式的一次能耗,且运行费用低于目前的按面积收费标准,指出低环境温度空气源热泵具有推广使用价值。     

废热驱动热管溴化锂制冷机的比较

利用热力学第一定律的热力平衡方法和热力学第二定律的火用分析方法,分别对单级单效、单级双效和两级热管废热回收双效溴化锂制冷系统的热力系数和火用效率进行比较。结果表明：不管从热经济性角度,还是从能源利用的完善性（[火用]效率）与合理性（能级匹配）角度,两级热管废热回收双效溴化锂制冷系统都更具合理性和实用性。     

Development of a fixed bed absorption refrigerator with high power density for the use of low grade heat sources

The low efficiency and the high cost of sorption systems with small or medium cooling capacity have until now impeded their widespread application except in recreational vehicles. The comparison of the most enticing sorption systems shows that both—a simple concept and low driving temperatures—can be realised with ammoniated salts. The development of a new, highly efficient, heat exchanger facilitates the attainment of an average cooling power of up to 200 W_{ref. capacity} per litre_{reaction vessel} in a quasi-continuous process. High power density and good dynamic behaviour characterise the system and make it an attractive ecological and economical alternative.     

Performance enhancement of a household refrigerator by addition of latent heat storage

This paper studies the effect of adding a phase change material (PCM) slab on the outside face of a refrigerator evaporator. A dynamic model of the vapour compression cycle including the presence of the phase change material and its experimental validation is presented. The simulation results of the system with PCM show that the addition of thermal inertia globally enhances heat transfer from the evaporator and allows a higher evaporating temperature, which increases the energy efficiency of the system. The energy stored in the PCM is yielded to the refrigerator cell during the off cycle and allows for several hours of continuous operation without power supply.