Experimental investigation of flow boiling heat transfer characteristics of FC-72 in cross-linked microchannel heat sinks using thermochromatic liquid crystals

Ayman Megahed, Ibrahim Hassan, Kristina Cook

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

Abstract

The present study investigates the effect of cross-links on flow boiling heat transfer characteristics in rectangular microchannel heat sinks, using FC-72 as the working fluid. The silicon test section consists of 45 cross-linked microchannels, measuring 16 mm in length, with a hydraulic diameter of 248 μm. The parameters investigated include mass flux, heat flux, and exit quality, ranging from 99-275 kg/m2s, 7.2-88.8 kW/m2, and 0.01-0.71, respectively. Thermochromatic liquid crystals have been used in the present study as full-field surface temperature sensors to map the temperature distribution on the heat sink surface. The flow boiling heat transfer coefficient shows a different trend in the cross-linked design relative to the straight microchannel design. The flow boiling heat transfer coefficient increases with increasing exit quality at a constant mass flux, which is caused by the domination of the nucleation boiling mechanism in the cross-link region. The predictions obtained from the existing heat transfer correlations found in the literature significantly under-estimate the present heat transfer measurements, except for the Yu et al. (2002) correlation.

Original languageEnglish
Title of host publicationProceedings of the ASME Micro/Nanoscale Heat and Mass Transfer International Conference 2009, MNHMT2009
Pages1-7
Number of pages7
Volume2
DOIs
Publication statusPublished - 2010
Externally publishedYes
EventASME 2009 Micro/Nanoscale Heat and Mass Transfer International Conference 2009, MNHMT2009 - Shanghai, China
Duration: 18 Dec 200921 Dec 2009

Other

OtherASME 2009 Micro/Nanoscale Heat and Mass Transfer International Conference 2009, MNHMT2009
CountryChina
CityShanghai
Period18/12/0921/12/09

Fingerprint

Liquid Crystals
Heat sinks
Microchannels
Liquid crystals
Boiling liquids
Heat transfer
Heat transfer coefficients
Mass transfer
Silicon
Temperature sensors
Heat flux
Temperature distribution
Nucleation
Hydraulics
Fluids
fluorocarbon 72

ASJC Scopus subject areas

  • Fluid Flow and Transfer Processes

Cite this

Megahed, A., Hassan, I., & Cook, K. (2010). Experimental investigation of flow boiling heat transfer characteristics of FC-72 in cross-linked microchannel heat sinks using thermochromatic liquid crystals. In Proceedings of the ASME Micro/Nanoscale Heat and Mass Transfer International Conference 2009, MNHMT2009 (Vol. 2, pp. 1-7) https://doi.org/10.1115/MNHMT2009-18010

Experimental investigation of flow boiling heat transfer characteristics of FC-72 in cross-linked microchannel heat sinks using thermochromatic liquid crystals. / Megahed, Ayman; Hassan, Ibrahim; Cook, Kristina.

Proceedings of the ASME Micro/Nanoscale Heat and Mass Transfer International Conference 2009, MNHMT2009. Vol. 2 2010. p. 1-7.

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

Megahed, A, Hassan, I & Cook, K 2010, Experimental investigation of flow boiling heat transfer characteristics of FC-72 in cross-linked microchannel heat sinks using thermochromatic liquid crystals. in Proceedings of the ASME Micro/Nanoscale Heat and Mass Transfer International Conference 2009, MNHMT2009. vol. 2, pp. 1-7, ASME 2009 Micro/Nanoscale Heat and Mass Transfer International Conference 2009, MNHMT2009, Shanghai, China, 18/12/09. https://doi.org/10.1115/MNHMT2009-18010
Megahed A, Hassan I, Cook K. Experimental investigation of flow boiling heat transfer characteristics of FC-72 in cross-linked microchannel heat sinks using thermochromatic liquid crystals. In Proceedings of the ASME Micro/Nanoscale Heat and Mass Transfer International Conference 2009, MNHMT2009. Vol. 2. 2010. p. 1-7 https://doi.org/10.1115/MNHMT2009-18010
Megahed, Ayman ; Hassan, Ibrahim ; Cook, Kristina. / Experimental investigation of flow boiling heat transfer characteristics of FC-72 in cross-linked microchannel heat sinks using thermochromatic liquid crystals. Proceedings of the ASME Micro/Nanoscale Heat and Mass Transfer International Conference 2009, MNHMT2009. Vol. 2 2010. pp. 1-7
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