Efficiency enhancement of a loop thermosyphon on a mixed-wettability evaporator surface

Hongbin He, Kento Furusato, Masayuki Yamada, Biao Shen, Sumitomo Hidaka, Masamichi Kohno, Koji Takahashi, Yasuyuki Takata

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

This study presents an experimental investigation of the heat transfer performance of a two-phase loop thermosyphon with an enhanced mixed-wettability evaporator surface at sub-atmospheric pressures. For central-processing-unit (CPU) cooling applications, a lowering of the saturation temperature (pressure) is essential when water is used as the working fluid. Compared with copper mirror surfaces, up to over 100% enhancement of high heat transfer coefficient (HTC) was observed using surfaces with spotted wettability patterns, which consists of hydrophobic spots with contact angle ranged from 145° to 150°. The results revealed that the boiling behaviors changed drastically with the application of hydrophobic spots coating by artificially increasing the nucleation site density. Parametric tests with a variety of operating conditions, including different filling ratios, condenser temperatures, and heat loads revealed the minimum thermal resistance (i.e., the optimum thermosyphon performance) to be 0.03 K/W on the boiling side.

Original languageEnglish
Pages (from-to)1245-1254
Number of pages10
JournalApplied Thermal Engineering
Volume123
DOIs
Publication statusPublished - Jan 1 2017

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Thermosyphons
Evaporators
Wetting
Boiling liquids
Thermal load
Heat resistance
Heat transfer coefficients
Atmospheric pressure
Contact angle
Program processors
Mirrors
Nucleation
Heat transfer
Cooling
Copper
Coatings
Temperature
Fluids
Water

All Science Journal Classification (ASJC) codes

  • Energy Engineering and Power Technology
  • Industrial and Manufacturing Engineering

Cite this

Efficiency enhancement of a loop thermosyphon on a mixed-wettability evaporator surface. / He, Hongbin; Furusato, Kento; Yamada, Masayuki; Shen, Biao; Hidaka, Sumitomo; Kohno, Masamichi; Takahashi, Koji; Takata, Yasuyuki.

In: Applied Thermal Engineering, Vol. 123, 01.01.2017, p. 1245-1254.

Research output: Contribution to journalArticle

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AU - Hidaka, Sumitomo

AU - Kohno, Masamichi

AU - Takahashi, Koji

AU - Takata, Yasuyuki

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