Experimental investigation on the small LiBr absorption refrigeration system with capillary mat terminal under various operating conditions

doi:10.16085/j.issn.1000-6613.2018-0578

Abstract

Abstract: Experiments were performed on a small LiBr absorption refrigeration system using capillary mat as the cooling terminal. The effects of heat source temperature and flow rates, cooling water flow rates, and chilled water on the unit performance, chilled water supply temperature and indoor temperature were analyzed. The optimal system performance was obtained under the following operating conditions:the heat source water temperature of 90-92℃, the heat source water flow rate of 1.5m³/h, cooling water flow rate of 4m³/h, and chilled water flow rate of 2.5m³/h. The results also showed that the increase of heat source water temperature and cooling water flow rate improved the cooling capacity significantly, and decreased the chilled water supply temperature, which might cause indoor dew condensation. The heat source water flow rate had little effect on the cooling capacity and chilled water temperature, which was not suitable as the regulation basis. Changing the chilled water flow rate is an effective way for regulating cooling capacity and preventing indoor dew condensation since the cooling capacity and chilled water supply temperature respectively increased by 92.1% and 1℃ (from 16.7℃ to 17.7℃) when the chilled water flow rate increased from 1.0m³/h to 2.5m³/h. The present results provided the evidences for the application and regulation of small solar LiBr absorption refrigeration system with capillary mat terminal.

Key words: lithium bromide, absorption refrigeration, capillary mat, solar energy, cooling capacity, performance

摘要： 对毛细管网为末端的小型溴化锂吸收式制冷系统进行实验研究，分析了不同热源水温度、热源水流量、冷却水流量和冷媒水流量分别对溴冷机性能、冷媒水供水温度以及房间温度的影响。实验得出该系统相对较优外部工况为：热源水温度90~92℃，热源水流量1.5m³/h，冷却水流量4m³/h，冷媒水流量2.5m³/h。实验结果表明，提高热源水温度和冷却水流量可以明显增大机组供冷量，但也存在冷媒水供水温度降低，可能造成结露的问题；热源水流量对机组制冷量和冷媒水供水温度影响较小，不适于作为动态调节的依据；改变冷媒水流量是调节系统供冷能力和避免结露的有效手段，冷媒水流量从1.0m³/h升高到2.5m³/h，制冷量升高92.1%，冷媒水供水温度也从16.7℃上升到17.7℃。实验为今后以毛细管网为末端的小型太阳能溴化锂吸收式制冷系统应用调节提供依据和指导。

关键词: 溴化锂, 吸收式制冷, 毛细管网, 太阳能, 制冷量, 性能

CLC Number:

ZHU Maochuan, ZHOU Guobing. Experimental investigation on the small LiBr absorption refrigeration system with capillary mat terminal under various operating conditions[J]. Chemical Industry and Engineering Progress, 2018, 37(12): 4646-4653.

朱茂川, 周国兵. 毛细管网为末端的小型溴化锂吸收式制冷系统变工况实验研究[J]. 化工进展, 2018, 37(12): 4646-4653.

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