[1] Yu Ping, Zhang Hong, Xu Hui, et al. Numerical simulation for solid-liquid phase changeof metal sodium in combined wick [J]. Journal of Southeast University (English Edition), 2014, 30 (4): 456-461. [doi:10.3969/j.issn.1003-7985.2014.04.010]

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Numerical simulation for solid-liquid phase changeof metal sodium in combined wick()

组合式吸液芯内金属钠固-液相变的数值模拟

Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

Volumn:

30

Issue:

2014 4

Page:

456-461

Research Field:

Energy and Power Engineering

Publishing date:

2014-12-31

Info

Title:

Numerical simulation for solid-liquid phase changeof metal sodium in combined wick

组合式吸液芯内金属钠固-液相变的数值模拟

Author(s):

Yu Ping¹, Zhang Hong^{1, 2}, Xu Hui¹, Shen Yan¹

¹College of Energy, Nanjing University of Technology, Nanjing 211816, China
²Changzhou Institute of Technology, Changzhou 213002, China

于萍¹, 张红^{1, 2}, 许辉¹, 沈妍¹

¹南京工业大学能源学院, 南京 211816; ²常州工学院, 常州 213002

Keywords:

solid-liquid phase change;  combined wick;  sodium;  porous media

固-液相变;  组合式吸液芯;  金属钠;  多孔介质

PACS:

TK172.4

DOI:

10.3969/j.issn.1003-7985.2014.04.010

Abstract:

Based on the finite volume method and the enthalpy-porous model, the solid-liquid phase change of sodium in the combined wick is numerically studied. The one-temperature model is used since the thermal conductivity of sodium is close to that of the combined wick materials. The non-Darcy law and natural convection in the melting process are taken into account. The results show that a thin metal fiber felt in the combined wick can result in a faster melting rate of the sodium and a shorter time for the molten sodium to reach the maximum velocity, which can shorten the time for the high-temperature heat pipe startup. A thick metal fiber felt in the combined wick can result in a uniform temperature distribution in the vertical heating wall and a small wall temperature difference, which can reduce the possibility of an overheat spot.

采用有限容积法和焓-多孔介质模型数值模拟了组合式吸液芯内金属钠熔化的固-液相变过程.由于液态金属钠和组合式吸液芯的导热系数在同一数量级, 因而采用单温度模型, 模拟过程中考虑了非达西效应影响和液态金属钠的自然对流现象.研究结果发现, 组合式吸液芯中金属纤维毡厚度越小, 金属钠受热熔化的速度越快, 且熔化后的液态钠流速达到最大值所用的时间越短, 进而可以缩短热管启动时间;组合式吸液芯中金属纤维毡厚度越大, 竖直加热壁面的温度分布越均匀、壁面温差越小, 进而减少了加热壁面产生过热点的可能.

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Memo

Memo:

Biographies: Yu Ping(1985—), female, graduate; Zhang Hong(corresponding author), female, doctor, professor, hzhang@njut.edu.cn.
Foundation items: The National Natural Science Foundation of China(No.51076062), the Scientific Innovation Research of College Graduates in Jiangsu Province(No.CXZZ12_0421).
Citation: Yu Ping, Zhang Hong, Xu Hui, et al.Numerical simulation for solid-liquid phase change of metal sodium in combined wick[J].Journal of Southeast University(English Edition), 2014, 30(4):456-461.[doi:10.3969/j.issn.1003-7985.2014.04.010]

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