Che-Yin Lee This email address is being protected from spambots. You need JavaScript enabled to view it.1, Hsin-Heng Huang2, Shi-Min Lee2 and Kwan Ouyang3
1Department of Mechanical and Electro-Mechanical Engineering, Tamkang University, Tamsui, Taiwan 251, R.O.C. 2Department of Aerospace Engineering, Tamkang University, Tamsui, Taiwan 251, R.O.C. 3Department of Marine Engineering, Taipei College of Maritime Technology, Taipei, Taiwan, R.O.C.
Received: August 5, 2014 Accepted: November 13, 2014 Publication Date: December 1, 2014
This study used numerical simulation to analyze the influence of different factors, such as vacuum degree, fill ratio and aspect ratio, on the heat transfer characteristics of low-watt thermosyphon in natural convection. The mass and energy source terms were added in the continuity and energy equation to simulate the exchanges between vapor and liquid phases. The comparison analysis of computed result and experiment data showed that the numerical model used in this study is appropriate to analyze the physical mechanism and heat transfer property of thermosyphon. The results confirmed that low vacuum degree and long evaporator characterize better thermal resistance. The optimal fill ratio was 60% when the vacuum degree was 35 torr and the aspect ratio was 11.8.
Keywords: Heat Pipe, Thermosyphon, Vacuum Degree, Fill Ratio, Aspect Ratio, Boiling Heat Transfer
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