A loop thermosyphon with hydrophobic spots evaporator surface

Hongbin He, Biao Shen, Sumitomo Hidaka, Koji Takahashi, Yasuyuki Takata

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Heat transfer characteristic of a closed two-phase thermosyphon with enhanced boiling surface is studied and compared with that of a copper mirror surface. Two-phase cooling improves heat transfer coefficient (HTC) a lot compared to single-phase liquid cooling. The evaporator surfaces, coated with a pattern of hydrophobic circle spots (non-electroplating Ni-PTFE, 0.5~2 mm in diameter and 1.5-3 mm in pitch) on Cu substrates, achieve very high heat transfer coefficient and lower the incipience temperature overshoot using water as the working fluid. Sub-atmospheric boiling on the hydrophobic spot-coated surface shows a much better heat transfer performance. Tests with heat loads (30 W to 260 W) reveals the coated surfaces enhance nucleate boiling performance by increasing the bubbles nucleation sites density. Hydrophobic circle spots coated surface with diameter 1 mm, pitch 1.5 mm achieves the maximal heat transfer enhancement with the minimum boiling thermal resistance as low as 0.03 K/W. The comparison of three evaporator surfaces with same spot parameters but different coating materials is carried out experimentally. Ni-PTFE coated surface with immersion method performs the optimal performance of the thermosyphon.

Original languageEnglish
Title of host publicationASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018
PublisherAmerican Society of Mechanical Engineers (ASME)
ISBN (Print)9780791851197
Publication statusPublished - Jan 1 2018
EventASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018 - Dubrovnik, Croatia
Duration: Jun 10 2018Jun 13 2018

Publication series

NameASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018

Other

OtherASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018
CountryCroatia
CityDubrovnik
Period6/10/186/13/18

Fingerprint

Thermosyphons
Evaporators
Boiling liquids
Heat Transfer Coefficient
Polytetrafluoroethylene
Heat transfer
Polytetrafluoroethylenes
Heat transfer coefficients
Cooling
Heat Transfer
Circle
Heat Transfer Enhancement
Thermal Resistance
Nucleate boiling
Overshoot
Thermal load
Immersion
Nucleation
Heat resistance
Copper

All Science Journal Classification (ASJC) codes

  • Process Chemistry and Technology
  • Fluid Flow and Transfer Processes
  • Modelling and Simulation

Cite this

He, H., Shen, B., Hidaka, S., Takahashi, K., & Takata, Y. (2018). A loop thermosyphon with hydrophobic spots evaporator surface. In ASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018 (ASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018). American Society of Mechanical Engineers (ASME).

A loop thermosyphon with hydrophobic spots evaporator surface. / He, Hongbin; Shen, Biao; Hidaka, Sumitomo; Takahashi, Koji; Takata, Yasuyuki.

ASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018. American Society of Mechanical Engineers (ASME), 2018. (ASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

He, H, Shen, B, Hidaka, S, Takahashi, K & Takata, Y 2018, A loop thermosyphon with hydrophobic spots evaporator surface. in ASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018. ASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018, American Society of Mechanical Engineers (ASME), ASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018, Dubrovnik, Croatia, 6/10/18.
He H, Shen B, Hidaka S, Takahashi K, Takata Y. A loop thermosyphon with hydrophobic spots evaporator surface. In ASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018. American Society of Mechanical Engineers (ASME). 2018. (ASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018).
He, Hongbin ; Shen, Biao ; Hidaka, Sumitomo ; Takahashi, Koji ; Takata, Yasuyuki. / A loop thermosyphon with hydrophobic spots evaporator surface. ASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018. American Society of Mechanical Engineers (ASME), 2018. (ASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2018).
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