Influence of changing evaporator/condenser section on operation characteristics of gravity heat pipe

doi:10.11949/j.issn.0438-1157.20161391

Abstract

Abstract:

The heat transfer characteristics of gravity heat pipes with different length and position of evaporator section and condenser section were investigated experimentally. The tested gravity heat pipes were all fabricated with copper tube and charged with distilled water. The heat pipe had the outer diameter of 9.52 mm with the thickness of 1.2 mm and total length of 250 mm. The experimental input power range was from 40 W to 160 W. The results showed that the length and the position of evaporator section and condenser section affected the heat transfer characteristics of gravity heat pipe. When moving up the evaporator section, the evaporator temperature was 1-6℃ lower. The thermal resistance and the evaporator temperature were decreased when moving down the condenser section. And the temperature difference between the condenser section and the adiabatic section was decreased by about 25%. Reducing the length of the condenser section or evaporator section had the negative influence on the heat transfer performance of a heat pipe, which should be restricted in the application of GHPs.

Key words: gravity heat pipe, heat transfer, thermal resistance, evaporation, condensation

摘要：

以铜-水重力热管为对象，研究了热管蒸发段和冷凝段的长度及位置等应用条件改变对重力热管传热性能的影响，实验输入功率范围为40~160 W。对比不同应用条件下热管的蒸发段温度、当量热阻、蒸发段和冷凝段分别与绝热段之间温差的变化规律得出结论：蒸发段和冷凝段长度及位置的改变能够影响重力热管的传热性能。冷凝段适当下移能使热管热阻减小，冷凝段和绝热段温差降低，蒸发段温度降低，热管传热性能改善，而冷凝段长度减小会对传热性能产生不利影响；加热段适当向冷凝端方向移动有利于热管的传热性能提升，蒸发段长度的减小对热管传热产生不利影响，实际应用中应避免。

关键词: 重力热管, 传热, 热阻, 蒸发, 凝结

CLC Number:

TK172.4

ZHANG Jingcao, XIN Gongming, CHEN Yan, CHENG Lin, JI Wanxiang. Influence of changing evaporator/condenser section on operation characteristics of gravity heat pipe[J]. CIESC Journal, 2017, 68(4): 1343-1348.

张劲草, 辛公明, 陈岩, 程林, 季万祥. 蒸发段和冷凝段变化对重力热管性能的影响[J]. 化工学报, 2017, 68(4): 1343-1348.

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