Effects of bending on heat transfer performance of axial micro-grooved heat pipe

Journal of Central South University of Technology (Impact Factor: 0.36). 01/2011; 18(2):580-586. DOI: 10.1007/s11771-011-0734-2

ABSTRACT Heat pipe is always bent in the typical application of electronic heat dissipation at high heat flux, which greatly affects
its heat transfer performance. The capillary limit of heat transport in the bent micro-grooved heat pipes was analyzed in
the vapor pressure drop, the liquid pressure drop and the interaction of the vapor with wick fluid. The bent heat pipes were
fabricated and tested from the bending angle, the bending position and the bending radius. The results show that temperature
difference and thermal resistance increase while the heat transfer capacity of the heat pipe decreases, with the increase
of the bending angles and the bending position closer to the vapor section. However, the effects of bending radius can be
ignored. The result agrees well with the predicted equations.

Key wordselectronics cooling system–axial micro-grooved heat pipe–bending–heat transfer performance

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