| 摘要: |
| 重力供液再循环蒸发器受到工作原理的限制，其流路结构不能借鉴直接膨胀供液系统蒸发器的流路结构。本文首先阐明了重力再循环制冷系统蒸发器流路的优化原则，设计了两种蒸发器流路结构，其中第一种为重力供液系统常用的流路结构，第二种为经过优化的流路结构，在此基础上搭建了重力再循环蒸发器实验台，通过实验对优化前后的蒸发器进行性能对比与分析。研究表明，在保温体温度一定的情况下，经过优化的蒸发器因其每个支路接触空气的平均温度相同，从而能保证并联四个支路制冷剂侧有相同的循环倍率和相同的平均传热温差，经过优化的蒸发器具有更好的性质，尤其在﹣25 ℃和﹣20 ℃工况下，第二种（改进型）蒸发器比第一种（传统型）蒸发器有更高的单位面积传热量，制冷量分别增大60.3%和44.1%，性能系数分别提高16%和13.8%。 |
| 关键词: 重力供液 蒸发器流路 蒸发器性能 再循环蒸发器 |
| DOI： |
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| Flow Path Optimization and Performance Study on Gravity Recirculation Evaporator |
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Zang Runqing, Zhao Dong, Liu Yazhe, Liu Jianxun, Zhang Zhu, Ji Weichuan
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| (Tianjin Key Laboratory of Refrigeration Technology, Tianjin University of Commerce, Refrigeration Engineering Research Center of Ministry of Education, Tianjin Refrigeration Engineering Technology Center) |
| Abstract: |
| As gravity-fed recirculation evaporator is restricted by its principles, the structure of its flow path couldn’t be the same as that of the direct expansion cooling system. Firstly, in this paper, the flow path optimal principles of gravity-fed recirculation evaporator have been clarified, and two forms of flow path structures have been designed. The first is a flow path structure which is commonly used in the gravity-fed cooling system, and the second is an optimized flow path structure. A gravity-fed recirculation evaporator experiment platform is built based on the above. The evaporator performances before and after the optimization have been compared and analyzed. Results shows that, when the temperature of the insulation body keeps constant, the same circulation ratio and mean temperature difference can be guaranteed at the refrigerant-side of the four branches in parallel since the mean temperature of the air which contacts each of the branches of the optimized evaporator is the same.It is also shown that the optimized evaporation has a better performance, especially under the low-temperature condition. The second (ie. the optimized) evaporator has a greater heat transfer than the first (ie. the common) one based on per unit area, and the cooling capacity increased 60.3% and 44.1% respectively, and the COP increased 16% and 13.87% respectively for the condition of -25 ℃ and -20 ℃. |
| Key words: gravity-fed recirculation evaporator flow path air evaporator performance recirculation evaporator |
