Research Papers: Evaporation, Boiling, and Condensation

An Experimental Investigation of Pressure Drop in Expanding Microchannel Arrays

[+] Author and Article Information
Mark J. Miner

e-mail: mark.miner@asu.edu

Patrick E. Phelan

e-mail: phelan@asu.edu

Carlos A. Ortiz

Mechanical Engineering,
Arizona State University,
Tempe, AZ 85281

1Corresponding author.

Contributed by the Heat Transfer Division of ASME for publication in the JOURNAL OF HEAT TRANSFER. Manuscript received January 26, 2013; final manuscript received August 21, 2013; published online November 21, 2013. Assoc. Editor: W. Q. Tao.

J. Heat Transfer 136(3), 031502 (Nov 21, 2013) (9 pages) Paper No: HT-13-1046; doi: 10.1115/1.4025557 History: Received January 26, 2013; Revised August 21, 2013

The pressure effects of expanding the cross section of microchannels along the direction of flow are investigated across four rates of channel expansion in the flow boiling of R-134a. Prior investigation by the authors detailed the fabrication of four copper microchannel arrays and the pumped-loop apparatus developed to facilitate interchange of the microchannel specimens, allowing consistency across experiments. Significant beneficial pressure effects are observed to result from the expansion, including reduction by half of the pumping cost per flow rate at critical heat flux. The improvements are seen with small expansions, and greater expansion yields diminishing returns. The high pressure drops associated with microchannel evaporators are effectively reduced by expanding channel geometry, and the low-frequency system spectral response indicates that expanding channel arrays typically carry less energy in oscillations up to 2.5 Hz, suggesting amelioration of oscillatory instabilities. Results are discussed in light of a comparative force analysis, with the balance of these forces linked to the observed behavior of the pressure drop and heat flux relationship.

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Miner, M. J., Phelan, P. E., Ortiz, C. A., and Odom, B. A., 2013, “Experimental Measurements of Critical Heat Flux in Expanding Microchannel Arrays,” ASME J. Heat Transfer, 135, p. 101501. [CrossRef]
Poiseuille, J.-L.-M., 1843, Recherches Expérimentales sur le Mouvement des Liquides Dans les Tubes de Très-Petits Diamétres, Comptes Rendus de l'Académie des Sciences, Paris.
Tuckerman, D. B., and Pease, R. F. W., 1981, “High-Performance Heat Sinking for VLSI,” IEEE Electron Device Lett., 2(5), pp. 126–129. [CrossRef]
El-Masri, M. A., and Louis, J. F., 1978, “On the Design of High-Temperature Gas Turbine Blade Water-Cooling Channels,” ASME J. Eng. Power, 100(4), pp. 586–591. [CrossRef]
Lockhart, R. W., and Martinelli, R. C., 1949, “Proposed Correlation of Data for Isothermal Two-Phase Two-Component Flow in Pipes,” J. Chem. Eng. Prog., 45(1), pp. 39–48.
Lazarek, G. M., and Black, S. H., 1982, “Evaporative Heat Transfer, Pressure Drop, and Critical Heat Flux in a Small Vertical Tube With R-113,” Int. J. Heat Mass Transfer, 25(7), pp. 945–960. [CrossRef]
Kandlikar, S. G., 2002, “Fundamental Issues Related to Flow Boiling in Minichannels and Microchannels,” Exp. Thermal Fluid Sci., 26(2), pp. 389–407. [CrossRef]
Revellin, R., and Thome, J. R., 2007, “Adiabatic Two-Phase Frictional Pressure Drops in Microchannels,” Exp. Therm. Fluid Sci., 31(7), pp. 673–685. [CrossRef]
Tran, T. N., Chyu, M. C., Wambsganss, M. W., and France, D. M., 2000, “Two-Phase Pressure Drop of Refrigerants During Flow Boiling in Small Channels: An Experimental Investigation and Correlation Development,” Int. J. Multiphase Flow, 26(11), pp. 1739–1754. [CrossRef]
Lee, P.-S., and Garimella, S. V., 2008, “Saturated Flow Boiling Heat Transfer and Pressure Drop in Silicon Microchannel Arrays,” Int. J. Heat Mass Transfer, 51(3), pp. 789–806. [CrossRef]
Harirchian, T., and Garimella, S. V., 2012, “Flow-Regime-Based Modeling of Heat Transfer and Pressure Drop in Microchannel Flow Boiling,” Int. J. Heat Mass Transfer, 55, pp. 1246–1260. [CrossRef]
Kuo, C.-J., and Peles, Y., 2009, “Pressure Effects on Flow Boiling Instabilities in Parallel Microchannels,” Int. J. Heat Mass Transfer, 52(1), pp. 271–280. [CrossRef]
Mishima, K., and Hibiki, T., 1996, “Some Characteristics of Airwater Two-Phase Flow in Small Diameter Vertical Tubes,” Int. J. Multiphase Flow, 22(4), pp. 703–712. [CrossRef]
Lee, H. J., and Lee, S. Y., 2001, “Pressure Drop Correlations for Two Phase Flow Within Horizontal Rectangular Channels With Small Heights,” Int. J. Multiphase Flow, 27(5), pp. 783–796. [CrossRef]
Zhang, M., and Webb, R., 2001, “Correlation of Two-Phase Friction for Refrigerants in Small-Diameter Tubes,” Exp. Therm. Fluid Sci., 25(3), pp. 131–139. [CrossRef]
Mudawar, I., 2011, “Two-Phase Microchannel Heat Sinks: Theory, Applications, and Limitations,” ASME J. Electron. Packag., 133(4), p. 041002. [CrossRef]
Chen, T., and Garimella, S. V., 2012, “A Study of Critical Heat Flux During Flow Boiling in Microchannel Heat Sinks,” ASME J. Heat Transfer, 134(1), p. 011504. [CrossRef]
Odom, B. A., Miner, M. J., Ortiz, C. A., Sherbeck, J., Prasher, R., and Phelan, P. E., 2012, “Microchannel Two-Phase Flow Oscillation Control with an Adjustable Inlet Orifice,” ASME J. Heat Transfer, 134(12), p. 122901. [CrossRef]
Koşar, A., Kuo, C.-J., and Peles, Y., 2006, “Suppression of Boiling Flow Oscillations in Parallel Microchannels by Inlet Restrictors,” ASME J. Heat Transfer, 128(3), pp. 251–260. [CrossRef]
Kandlikar, S. G., Kuan, W. K., Willistein, D. A., and Borrelli, J., 2006, “Stabilization of Flow Boiling in Microchannels Using Pressure Drop Elements and Fabricated Nucleation Sites,” ASME J. Heat Transfer, 128(4), pp. 389–397. [CrossRef]
Basu, S., Ndao, S., Michna, G. J., Peles, Y., and Jensen, M. K., 2011, “Flow Boiling of R134a in Circular Microtubes—Part II: Study of Critical Heat Flux Condition,” ASME J. Heat Transfer, 133(5), p. 051503. [CrossRef]
Hwang, J., Tseng, F., and Pan, C., 2005, “Ethanol—CO2 Two-Phase Flow in Diverging and Converging Microchannels,” Int. J. Multiphase Flow, 31(5), pp. 548–570. [CrossRef]
Mukherjee, A., and Kandlikar, S. G., 2009, “The Effect of Inlet Constriction on Bubble Growth During Flow Boiling in Microchannels,” Int. J. Heat Mass Transfer, 52(21), pp. 5204–5212. [CrossRef]
Mukherjee, A., and Kandlikar, S. G., 2005, “Numerical Study of the Effect of Inlet Constriction on Bubble Growth During Flow Boiling in Microchannels,” International Conference on Microchannels and Minichannels ICMM2005-75143, ASME.
Lee, P. C., and Pan, C., 2007, “Boiling Heat Transfer and Two-Phase Flow of Water in a Single Shallow Microchannel With a Uniform or Diverging Cross Section,” J. Micromech. Microeng., 18(2), p. 025005. [CrossRef]
Lu, C. T., and Pan, C., 2008, “Stabilization of Flow Boiling in Microchannel Heat Sinks With a Diverging Cross-Section Design,” J. Micromech. Microeng., 18(7), p. 075035. [CrossRef]
Lu, C. T., and Pan, C., 2009, “A Highly Stable Microchannel Heat Sink for Convective Boiling,” J. Micromech. Microeng., 19(5), p. 055013. [CrossRef]
Lu, C. T., and Pan, C., 2011, “Convective Boiling in a Parallel Microchannel Heat Sink With a Diverging Cross Section and Artificial Nucleation Sites,” Exp. Therm. Fluid Sci., 35(5), pp. 810–815. [CrossRef]
Balasubramanian, K., Lee, P. C., Jin, L., Chou, S., Teo, C., and Gao, S., 2011, “Experimental Investigations of Flow Boiling Heat Transfer and Pressure Drop in Straight and Expanding Microchannels: A Comparative Study,” Int. J. Therm. Sci., 50(12), pp. 2413–2421. [CrossRef]
Liu, T.-L., Fu, B.-R., and Pan, C., 2012, “Boiling Two-Phase Flow and Efficiency of Co- and Counter-Current Microchannel Heat Exchangers With Gas Heating,” Int. J. Heat Mass Transfer, 55(21–22), pp. 6130–6141. [CrossRef]
Miner, M. J., and Phelan, P. E., “Effect of Cross-Sectional Perturbation on Critical Heat Flux Criteria in Microchannels,” ASME J. Heat Transfer (in press).
MATLAB, 2010, Version 7.13.0 (R2011b), The MathWorks Inc., Natick, MA.
Kandlikar, S. G., 2010, “Scale Effects on Flow Boiling Heat Transfer in Microchannels: A Fundamental Perspective,” Int. J. Therm. Sci., 49(7), pp. 1073–1085. [CrossRef]
Young, T., 1805, “An Essay on the Cohesion of Fluids,” Philos. Trans. R. Soc. London, 95, pp. 65–87. [CrossRef]
Laplace, P. S., 1829, Méchanique Céleste, Hilliard, Gray, Little, and Wilkins, Boston, MA.


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Fig. 1

Microchannel turret

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Fig. 3

Juxtaposed 1 deg inlet and outlet

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Fig. 4

Cross section of apparatus (from Ref. [1])

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Fig. 5

Flow loop schematic

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Fig. 6

Pressure curves at CHF with error bars

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Fig. 7

Slopes of pressure curves at CHF with 95% fit confidence bounds

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Fig. 8

Outlet quality at CHF

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Fig. 9

Power spectral densities of pressure drop (frequency in HZ on abscissa, normalized PSD on ordinate)

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Fig. 10

Heat flux effect on pressure drop

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Fig. 11

Representative force scales in 10 mm long microchannels with 3gs R-134 a at 350kPa,x = 0.5,q· = 500 (W/cm2)



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