| 摘要: |
| 吸收式制冷作为最早的人工制冷方法，诞生至今已有200多年。真正意义上民用和工业应用有60多年，近20余年来，吸收式制冷在理论与应用等方面都取得了迅速发展，并在制冷机市场上占有相当的份额，得到国内外厂商和学者的广泛关注与研究。随着人类能源消耗量的不断增加，需要进一步深入研究新能源、分布式能源及能源的高效利用。余热、废热、可再生的太阳能、地热能等的利用使得热能驱动的吸收式制冷（热泵）技术得到越来越多的关注。与采用电驱动蒸气机械压缩式制冷（热泵）系统不同，吸收式制冷（热泵）技术可利用采用低品位热源的热能直接驱动，运行成本远低于电驱动系统。吸收式系统多采用H2O-LiBr溶液、NH3-H2O溶液等自然工质作为冷媒，具有环境友好特性，同时具有安全，可以无噪音运行，可靠性高等显著优点。但同时具有占地面积大、初投资高，冷却负荷高，一次能源效率低（直燃形式）等不足。针对这些特性，现阶段的主要的研究方向包括：循环设计优化、工质对选择、系统部件热质传递强化、系统控制策略优化等。狭义的吸收式循环是指闭式、溶液吸收制冷剂蒸气的吸收式制冷（热泵）循环。该类循环按照循环形式分类包括单吸收循环、多吸收循环和复合循环。单吸收循环主要包括基本单效吸收循环、扩散吸收循环、膜吸收循环、热变换器循环、重力驱动的阀切换循环以及自复叠循环；多吸收循环主要包括再吸收循环、多效循环、中间效循环、多级循环、中间级循环以及GAX循环；复合循环主要包括喷射-吸收复合、压缩-吸收复合和膨胀-吸收复合等复合形式。现有吸收式制冷技术研究热点主要包括且不局限于太阳能、中低温余热利用、冷热电联产、储能（蓄冷、蓄热），膜交换材料、高温下耐腐蚀材料，塑料热交换器等方面。吸收式循环现有循环结构的提出针对的是一定温度和浓度下循环，面对新的应用场景、新材料以及新吸收工质对，吸收式循环可以提出多种更高效、更宽热源驱动温度范围和溶液浓度范围的新循环。 |
| 关键词: 制冷循环 吸收式制冷 溴化锂 氨水 进展 综述 |
| DOI： |
| 投稿时间：2016-09-28
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| 基金项目:国家重点研发计划课题（2016YFB0901404）项目资助。 |
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| State-of-the-art Absorption Refrigeration and Heat Pump Cycles |
| Chen Guangming,Shi Yuqi |
| (Key Laboratory of Refrigeration and Cryogenic Technology in Zhejiang Province, Institute of Refrigeration and Cryogenics, Zhejiang University) |
| Abstract: |
| As the first artificial refrigeration method developed, absorption refrigeration has been around for more than 200 years. In truth, it has been used in civil and industrial applications for more than 60 years. Absorption refrigeration has developed rapidly in terms of theory and application over the past 20 years, and in the refrigerator market occupies a considerable share, has drawn significant attention from both domestic and foreign manufacturers. With an increase in human energy consumption, in-depth research on new and distributed energy sources and their efficient utilization needs to be carried out. The use of waste heat, renewable solar energy, and geothermal energy make heat-driven refrigeration (heat pumps) an increasingly attractive option.Unlike electric-driven vapor compression refrigeration (heat pump) systems, absorption refrigeration (heat pump) technology can be driven directly using thermal energy from low-grade heat sources, operating at a much lower cost than the electric-driven system. Owing to their environmentally friendly features, including safety, noise-free operation, high reliability, and other significant advantages, absorption systems have adopted a water-lithium bromide solution, an ammonia-ammonia solution, or other natural refrigerant as the working fluid. However, absorption systems have a large footprint, a large initial investment, high cooling load, low energy efficiency (direct combustion form), and other deficiencies. In view of these characteristics, the main research directions at this stage include an optimization of the cycle design, the selection of a working fluid, enhancement of the heat and mass transfer of the system components, and optimization of the system control strategy.The absorption cycle, in a narrow sense, refers to a closed, vapor refrigerant absorbed by the solution refrigeration (heat pumps) cycle. This family of cycle, in accordance with its classification of cycle configuration, includes single absorption cycles, multi-absorption cycles, and combined cycles. Single absorption cycles consist of a basic single-effect absorption cycle, diffusion absorption cycles, membrane absorption cycles, heat booster cycles, gravity-driven valve-operation cycles, and self-cascade cycles. A multiple absorption cycle mainly includes a reabsorption cycle, multi-effect cycles, intermediate-effect cycles, multi-stage cycles, intermediate-stage cycles, and GAX cycles. Combined cycles mainly consist of ejection-absorption cycles, compression-absorption cycles, and expansion-absorption cycles.Existing research into absorption refrigeration technologies includes, but is not limited to, solar energy, medium and low temperature level waste heat utilization, combined heat and power, energy storage (cooling and heat storage), membrane exchange materials, high-temperature corrosion-resistant materials, plastic heat exchangers and so on. The existing absorption cycle was designed to satisfy a certain temperature and concentration range. In the face of new applications, new materials and a new absorption of working fluids, novel absorption cycles can be proposed with greater efficiency, wider ranges of heat-source driven temperature and solution concentration. |
| Key words: refrigeration cycle absorption refrigeration lithium bromide ammonia-water progress review |
