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Heat Pipe Science and Technology, An International Journal

ISSN Imprimir: 2151-7975
ISSN On-line: 2151-7991

Archives: Volume 1, 2010 to Volume 8, 2017

Heat Pipe Science and Technology, An International Journal

DOI: 10.1615/HeatPipeScieTech.2017018793
pages 1-12

FLUID FLOW AND HEAT TRANSFER CHARACTERISTICS OF A JEST-TYPE LOOP THERMOSYPHON

Ayaka Suzuki
Department of Advanced Mechanical Systems, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, Japan
Kaoru Sato
Department of Advanced Mechanical Systems, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, Japan
Yasushi Koito
Department of Advanced Mechanical Systems, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, Japan
Toshio Tomimura
Department of Advanced Mechanical Systems, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, Japan

RESUMO

A JEST-type loop thermosyphon has new mechanisms: a check valve is located between the liquid line and the evaporator, and a jet induction tube is located in the evaporator. These mechanisms aim at inducting the jet stream in the evaporator for exceeding the cooling performance of conventional thermosyphons. Fundamental experiments were conducted on the operational characteristics and the cooling performance of a loop thermosyphon. In this study, the experiments were carried out by changing the heat source size as 1.77 cm2, 4.15 cm2, and 7.07 cm2. From the results, it is confirmed that, irrespective of the heat source sizes, the loop thermosyphon promptly responds to the change in the heat transfer rate. As expected, the heated surface temperature is affected by the heat source sizes; however, the other temperatures and the circulating mass flow rate of the working fluid are hardly affected by the heat source size. In addition, it is also revealed that the heat transfer coefficient at the evaporator is greatly higher than that of conventional thermosyphons. Moreover, the quality and the void fraction of the working fluid were evaluated, and the fluid flow characteristics in the vapor line were also discussed.