TY - JOUR
T1 - Efficiency enhancement of a loop thermosyphon on a mixed-wettability evaporator surface
AU - He, Hongbin
AU - Furusato, Kento
AU - Yamada, Masayuki
AU - Shen, Biao
AU - Hidaka, Sumitomo
AU - Kohno, Masamichi
AU - Takahashi, Koji
AU - Takata, Yasuyuki
PY - 2017/1/1
Y1 - 2017/1/1
N2 - 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.
AB - 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.
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U2 - 10.1016/j.applthermaleng.2017.05.145
DO - 10.1016/j.applthermaleng.2017.05.145
M3 - Article
AN - SCOPUS:85020309332
VL - 123
SP - 1245
EP - 1254
JO - Applied Thermal Engineering
JF - Applied Thermal Engineering
SN - 1359-4311
ER -