Study on Heat Transfer Properties of Flat Heat Pipe with Conical Capillary Wicks

doi:10.3901/JME.2015.24.132

Abstract

Abstract: With the development of mechanical and electronic equipments, thermal management problem becomes more and more challenging. In order to solve this problem, according to the bionics principle, a new structure flat heat pipe(FHP), based on the micro structure of the Calathea zebrine, using nano-scale copper powder as sintered material, is constructed with conical capillary wicks, and its thermal performance is investigated experimentally with deionized water used as the working fluid. The effect of heating power, inclination angle and capillary wicks through oxidation on thermal performance of the FHP are studied. The results show that the existence of the multi-scale pore gap of the conical capillary wicks not only realized the vapor escape from large pore gap and liquid suck from small pore gap, but also shortened the liquid flow path, and reduced the flow resistance, as well as expanded the heat transfer area, thus greatly improved the heat transfer performance of the FHP. The new structure FHP has good thermal and anti-gravity performance. Capillary wicks through oxidation can significantly reduce the FHP’s thermal resistance, improving its thermal performance, and its minimum total thermal resistance is equal to 0.079 K/W when the heat flux reaches to 107.1 W/cm2.

Key words: capillary wick, conical, flat heat pipe, heat transfer, oxidation, thermal resistance

LI Hongchuan, JI Xianbing, ZHENG Xiaohuan, YANG Wolong, XU Jinliang. Study on Heat Transfer Properties of Flat Heat Pipe with Conical Capillary Wicks[J]. Journal of Mechanical Engineering, 2015, 51(24): 132-138.

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