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Research Papers

Effect of Meniscus Recession on the Effective Pore Radius and Capillary Pumping of Copper Metal Foams

[+] Author and Article Information
Mahmood R. S. Shirazy, Luc G. Fréchette

Department of Mechanical Engineering,
Institut Interdisciplinaire d'Innovation
Technologique—3IT,
Université de Sherbrooke,
Sherbrooke, PQ J1K2R1, Canada

Contributed by the Electronic and Photonic Packaging Division of ASME for publication in the JOURNAL OF ELECTRONIC PACKAGING. Manuscript received August 30, 2013; final manuscript received December 17, 2013; published online September 19, 2014. Assoc. Editor: Satish Chaparala.

J. Electron. Packag 136(4), 041003 (Sep 19, 2014) (8 pages) Paper No: EP-13-1098; doi: 10.1115/1.4026353 History: Received August 30, 2013; Revised December 17, 2013

An experimental study is performed to characterize the effect of meniscus recession on the effective pore radius and capillary pumping of copper metal foams which are to be used as wicks in heat pipes for electronic cooling. Knowledge of the effective pore radius is critical in defining the capillary pumping of a wicking material but is rarely measured under operating conditions. It is known that the meniscus of a liquid recedes when evaporating from a porous media, which could impact the effective pore radius and therefore the capillary pumping capabilities of the foam. To elucidate this impact, the evaporation rate is measured from foam strips wicking ethanol from a reservoir while applying heat fluxes to the foam. Using thermocouple and IR camera measurements, the measured evaporation rates are corrected to account for different thermal losses, including natural convection, direct thermal conduction to the liquid, and evaporation from the container. An analytical model is then developed to relate the evaporated mass to the maximum capillary pressure (minimum effective pore radius) provided by the foam. It is shown for the first time, that just before the onset of dryout, the recessed meniscus will lead to 15%, 28%, and 52% decrease in effective pore radius for samples with 68%, 75%, and 82% porosities, respectively. The capillary pumping therefore increases during evaporation. This can have significant impact on the prediction of the capillary limits in two phase capillary driven devices.

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References

Peterson, G. P., 1994, An Introduction to Heat Pipes: Modeling, Testing, and Applications, Wiley-Interscience, Hoboken, NJ, p. 368.
Shirazy, M. R. S., and Fréchette, L. G., 2010, “A Parametric Investigation of Operating Limits in Heat Pipes Using Novel Metal Foams as Wicks,” ASME 2010 3rd Joint U.S.-European Fluids Engineering Summer Meeting and 8th International Conference on Nanochannels, Microchannels, and Minichannels (FEDSM2010-ICNMM2010), Montreal, Canada, August 1–5, ASME Paper No. FEDSM-ICNMM2010-31268. [CrossRef]
Pilon, D., 2009, “High Heat Load Capacity Copper Foam Wick Structures,” AMD Technical Forum and Exposition, Taipei, Taiwan, October 20.
Migliaccio, C. P., and Garimella, S. V., 2011, “Evaporative Heat and Mass Transfer From the Free Surface of a Liquid Wicked Into a Bed of Spheres,” Int. J. Heat Mass Transfer, 54(15-16), pp. 3440–3447. [CrossRef]
Hanlon, M. A., and Ma, H. B., 2003, “Evaporation Heat Transfer in Sintered Porous Media,” ASME J. Heat Transfer, 125(4), pp. 644–652. [CrossRef]
Ranjan, R., Murthy, J. Y., and Garimella, S. V., 2011, “A Numerical Model for Transport in Flat Heat Pipes Considering Wick Microstructure Effects,” Int. J. Heat Mass Transfer, 54(1-3), pp. 153–168. [CrossRef]
Davis, T. W., and Garimella, S. V., 2008, “Thermal Resistance Measurement Across a Wick Structure Using a Novel Thermosyphon Test Chamber,” Exp. Heat Transfer, 21(2), pp. 143–154. [CrossRef]
Semenic, T., Lin, Y. Y., and Catton, I., 2008, “Use of Biporous Wicks to Remove High Heat Fluxes,” Appl. Therm. Eng., 28(4), pp. 278–283. [CrossRef]
Weibel, J. A., Garimella, S. V., and North, M. T., 2010, “Characterization of Evaporation and Boiling From Sintered Powder Wicks Fed by Capillary Action,” Int. J. Heat Mass Transfer, 53(19-20), pp. 4204–4215. [CrossRef]
Semenic, T., and Catton, I., 2009, “Experimental Study of Biporous Wicks for High Heat Flux Applications,” Int. J. Heat Mass Transfer, 52(21-22), pp. 5113–51121. [CrossRef]
Iverson, B. D., Davis, T. W., and Garimella, S. V., 2007, “Heat and Mass Transport in Heat Pipe Wick Structures,” J. Thermophys. Heat Transfer, 21(2), pp. 392–404. [CrossRef]
Faghri, A., 1995, Heat Pipe Science and Technology, Taylor & Francis Group, UK, pp. 854.
Pilon, D., Labbe, S., and Touzin, J., 2008, “Characterization of High Surface Area Open-Cell Metal Foams and Application to Thermal Management and Electrochemistry,” 5th International Conference on Porous Metals and Metallic Foams (MetFoam 2007), Montreal, Canada, September 5–7.
Berti, L. F., Santos, P. H. D., and Bazzo, E., 2011, “Evaluation of Permeability of Ceramic Wick Structures for Two Phase Heat Transfer Devices,” Appl. Therm. Eng., 31(6-7), pp. 1076–1081. [CrossRef]
Shirazy, M. R. S., and Frechette, L. G., 2013, “Capillary and Wetting Properties of Copper Metal Foams in the Presence of Evaporation and Sintered Walls,” Int. J. Heat Mass Transfer, 58(1-2), pp. 282–291. [CrossRef]
Li, C., and Peterson, G. P., 2006, “Evaporation/Boiling in Thin Capillary Wicks (II)—Effects of Volumetric Porosity and Mesh Size,” ASME J. Heat Transfer, 128(12), pp. 1320–1328. [CrossRef]
Shwin-Chung, W., and Yi-Huan, K., 2008, “Visualization and Performance Measurement of Operating Mesh-Wicked Heat Pipes,” Int. J. Heat Mass Transfer, 51(17-18), pp. 4249–4259. [CrossRef]
Jhan-Hong, L., Chia-Wei, C., and Chao, C., 2010, “Visualization and Thermal Resistance Measurement for the Sintered Mesh-Wick Evaporator in Operating Flat-Plate Heat Pipes,” Int. J. Heat Mass Transfer, 53(7-8), pp. 1498–1506. [CrossRef]
Shwin-Chung, W., Jhan-Hong, L., and Chia-Wei, C., 2009, “Evaporation Resistance Measurement With Visualization for Sintered Copper-Powder Evaporator in Operating Flat-Plate Heat Pipes,” 2009 4th International Microsystems, Packaging, Assembly and Circuits Technology Conference (IMPACT 2009), Taipei, Taiwan, October 21–23. [CrossRef]
Wong, S., and Lin, Y., 2011, “Effect of Copper Surface Wettability on the Evaporation Performance: Tests in a Flat-Plate Heat Pipe With Visualization,” Int. J. Heat Mass Transfer, 54(17-18), pp. 3921–3926. [CrossRef]
Shwin-Chung, W., and Chung-Wei, C., 2012, “Visualization and Evaporator Resistance Measurement for a Groove-Wicked Flat-Plate Heat Pipe,” Int. J. Heat Mass Transfer, 55(9-10), pp. 2229–2234. [CrossRef]
Fries, N., Odic, K., and Conrath, M., 2008, “The Effect of Evaporation on the Wicking of Liquids Into a Metallic Weave,” J. Colloid Interface Sci., 321(1), pp. 118–129. [CrossRef] [PubMed]
Adamson, A. W., and Gast, A. P., 1997, Physical Chemistry of Surfaces, Wiley-Interscience, Hoboken, NJ, pp. 808.

Figures

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Fig. 1

Morphology of the 75% porosity copper metal foams: (a) a macroscopic view of the copper metal foam; (b) capillary paths made by clusters of the spherical particles; and (c) small scale porosities formed between the spherical particles

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Fig. 2

Schematic drawing of (a) the heater block and thermocouple locations (dimensions in mm) and (b) measurement setup with IR camera

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Fig. 3

Comparison of input power and individual contribution of each heat transfer mode to the measured heat flow of the 68% porosity foam

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Fig. 4

Axial temperature distribution in metal foams of (a) 68% porosity, (b) 75% porosity, and (c) 82% porosity. x = 0 is in the liquid container.

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Fig. 5

Effect of (a) wall temperature and (b) heat flux on the evaporation rates of the different foam porosities

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Fig. 6

IR profile of the 75% porosity foam (a) the whole surface is wet (wetted length, x = 35 mm), (b) liquid front decreased to x = 23 mm from liquid surface, and (c) liquid front in x = 13 mm from liquid surface

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Fig. 7

(a) Values of calculated effective pore radius for different heat fluxes and (b) values of K/reff for different heat fluxes

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