Flow boiling heat transfer in a silicon microchannel heat sink using liquid crystal thermography

Ayman Megahed, Ibrahim Hassan, Tariq Ahmad

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

1 Citation (Scopus)

Abstract

The present study focuses on the experimental investigation of boiling heat transfer characteristics and pressure drop in a silicon microchannel heat sink. The microchannel heat sink consists of a rectangular silicon chip in which 45 rectangular microchannels were chemically etched with a depth of 295 μm, width of 254 μm, and a length of 16 mm. Un-encapsulated Thermochromic liquid Crystals (TLC) are used in the present work to enable nonintrusive and high spatial resolution temperature measurements. This measuring technique is used to provide accurate full and local surface-temperature and heat transfer coefficient measurements. Experiments are carried out for mass velocities ranging between 290 to 457 kg/m2.s and heat fluxes from 6.04 to 13.06 W/cm2 using FC-72 as the working fluid. Experimental results show that the pressure drop increases as the exit quality and the flow rate increase. High values of heat transfer coefficient can be obtained at low exit quality (xe<0.2). However, the heat transfer coefficient decreases sharply and remains almost constant as the quality increases for an exit quality higher than 0.2.

Original languageEnglish
Title of host publicationProceedings of the 6th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM2008
Pages551-560
Number of pages10
EditionPART A
DOIs
Publication statusPublished - 2008
Externally publishedYes
Event6th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM2008 - Darmstadt, Germany
Duration: 23 Jun 200825 Jun 2008

Other

Other6th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM2008
CountryGermany
CityDarmstadt
Period23/6/0825/6/08

Fingerprint

Heat sinks
Silicon
Microchannels
Boiling liquids
Heat transfer coefficients
Heat transfer
Pressure drop
Liquid Crystals
Temperature measurement
Liquid crystals
Heat flux
Flow rate
Fluids
Experiments
Temperature

ASJC Scopus subject areas

  • Process Chemistry and Technology

Cite this

Megahed, A., Hassan, I., & Ahmad, T. (2008). Flow boiling heat transfer in a silicon microchannel heat sink using liquid crystal thermography. In Proceedings of the 6th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM2008 (PART A ed., pp. 551-560) https://doi.org/10.1115/ICNMM2008-62071

Flow boiling heat transfer in a silicon microchannel heat sink using liquid crystal thermography. / Megahed, Ayman; Hassan, Ibrahim; Ahmad, Tariq.

Proceedings of the 6th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM2008. PART A. ed. 2008. p. 551-560.

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

Megahed, A, Hassan, I & Ahmad, T 2008, Flow boiling heat transfer in a silicon microchannel heat sink using liquid crystal thermography. in Proceedings of the 6th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM2008. PART A edn, pp. 551-560, 6th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM2008, Darmstadt, Germany, 23/6/08. https://doi.org/10.1115/ICNMM2008-62071
Megahed A, Hassan I, Ahmad T. Flow boiling heat transfer in a silicon microchannel heat sink using liquid crystal thermography. In Proceedings of the 6th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM2008. PART A ed. 2008. p. 551-560 https://doi.org/10.1115/ICNMM2008-62071
Megahed, Ayman ; Hassan, Ibrahim ; Ahmad, Tariq. / Flow boiling heat transfer in a silicon microchannel heat sink using liquid crystal thermography. Proceedings of the 6th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM2008. PART A. ed. 2008. pp. 551-560
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