The design and reliable operation of a two-phase micro-channel heat sink require a fundamental understanding of the complex transport phenomena associated with convective boiling in small, parallel coolant passages. This understanding is the primary goal of this paper. This goal is realized by exploring the following aspects of boiling in micro-channels: hydrodynamic instability, two-phase flow patterns, pressure drop, and convective boiling heat transfer. High-speed photographic methods were used to determine dominant flow patterns and explore as well as characterize hydrodynamic instabilities. Two types of dynamic instability were identified, a severe pressure drop oscillation and a mild parallel channel instability, and a simple method is recommended to completely suppress the former. Predictions of three popular two-phase pressure drop models and correlations were compared to micro-channel water data, and only a separated flow (Lockhart-Martinelli) correlation based on the assumption of laminar flow in both phases gave acceptable predictions. Several popular heat transfer correlations were also examined and deemed unsuitable for micro-channel heat sinks because all these correlations are based on turbulent flow assumptions, and do not capture the unique features of micro-channel flow such as abrupt transition to slug flow, hydrodynamic instability, and high droplet entrainment in the annular regime. These findings point to the need for further study of boiling behavior and new predictive tools specifically tailored to micro-channel heat sinks.
Issue Section:
Technical Papers
Keywords:
two-phase flow,
heat sinks,
boiling,
flow instability,
heat transfer,
laminar flow,
turbulence,
channel flow,
cooling
1.
Mudawar
, I.
, 2001
, “Assessment of High-Heat-Flux Thermal Management Schemes
,” IEEE Trans. Compon., Packag. Manuf. Technol., Part A
, 24
, pp. 122
–141
.2.
Tuckerman
, D. B.
, and Pease
, R. F. W.
, 1981
, “High-Performance Heat Sinking for VLSI
,” IEEE Electron Device Lett.
, EDL-Vol. 2
, pp. 126
–129
.3.
Phillips, R. J., 1990, “Micro-Channel Heat Sinks,” Advances in Thermal Modeling of Electronic Components, A. Bar-Cohen, and A. D. Kraus, eds., ASME Press, New York, 2, pp. 109–184.
4.
Knight
, R. W.
, Hall
, D. J.
, Goodling
, J. S.
, and Jaeger
, R. C.
, 1992
, “Heat Sink Optimization with Application to Microchannels
,” IEEE Trans. Compon., Hybrids, Manuf. Technol.
, 15
, pp. 832
–842
.5.
Weisberg
, A.
, Bau
, H. H.
, and Zemel
, J. N.
, 1992
, “Analysis of Microchannels for Integrated Cooling
,” Int. J. Heat Mass Transfer
, 35
, pp. 2465
–2474
.6.
Kawano, K., Minakami, K., Iwasaki, H., and Ishizuka, M., 1998, “Micro Channel Heat Exchanger for Cooling Electrical Equipment,” Proceedings of the ASME Heat Transfer Division, R. A. Nelson et al., eds., ASME, HTD-Vol. 361-3/PID-Vol. 3, pp. 173–180.
7.
Harms
, T. M.
, Kazmierczak
, M. J.
, and Cerner
, F. M.
, 1999
, “Developing Convective Heat Transfer in Deep Rectangular Microchannels
,” Int. J. Heat Fluid Flow
, 20
, pp. 149
–157
.8.
Fedorov
, A. G.
, and Viskanta
, R.
, 2000
, “Three-Dimensional Conjugate Heat Transfer in the Microchannel Heat Sink for Electronic Packaging
,” Int. J. Heat Mass Transfer
, 43
, pp. 399
–415
.9.
Qu
, W.
, and Mudawar
, I.
, 2002
, “Analysis of Three-Dimensional Heat Transfer in Micro-Channel Heat Sinks
,” Int. J. Heat Mass Transfer
, 45
, pp. 3973
–3985
.10.
Qu
, W.
, and Mudawar
, I.
, 2002
, “Experimental and Numerical Study of Pressure Drop and Heat Transfer in a Single-Phase Micro-Channel Heat Sink
,” Int. J. Heat Mass Transfer
, 45
, pp. 2549
–2565
.11.
Kennedy
, J. E.
, Roach
, Jr., G. M.
, Dowling
, M. F.
, Abdel-Khalik
, S. I.
, Ghiaasiaan
, S. M.
, Jeter
, S. M.
, and Quershi
, Z. H.
, 2000
, “The Onset of Flow Instability in Uniformly Heated Horizontal Microchannels
,” ASME J. Heat Transfer
, 122
, pp. 118
–125
.12.
Qu
, W.
, and Mudawar
, I.
, 2002
, “Prediction and Measurement of Incipient Boiling Heat Flux in Micro-Channel Heat Sinks
,” Int. J. Heat Mass Transfer
, 45
, pp. 3933
–3945
.13.
Bowers
, M. B.
, and Mudawar
, I.
, 1994
, “High Flux Boiling in Low Flow Rate, Low Pressure Drop Mini-Channel and Micro-Channel Heat Sinks
,” Int. J. Heat Mass Transfer
, 37
, pp. 321
–332
.14.
Bowers
, M. B.
, and Mudawar
, I.
, 1994
, “Two-Phase Electronic Cooling Using Mini-Channel and Micro-Channel Heat Sinks: Part 1-Design Criteria and Heat Diffusion Constraints
,” ASME J. Electron. Packag.
, 116
, pp. 290
–297
.15.
Bowers
, M. B.
, and Mudawar
, I.
, 1994
, “Two-Phase Electronic Cooling Using Mini-Channel and Micro-Channel Heat Sinks: Part 2-Flow Rate and Pressure Drop Constraints
,” ASME J. Electron. Packag.
, 116
, pp. 298
–305
.16.
Zhang, L., Koo, J. M., Jiang, L., Banerjee, S. S., Ashegi, M., Goodson, K. E., Santiago, J. G., and Kenny, T. W., 2000, “Measurement and Modeling of Two-Phase Flow in Microchannels with Nearly-Constant Heat Flux Boundary Conditions,” Micro-Electro-Mechanical Systems (MEMS)–2000, A. Lee et al., eds., ASME, MEMS-Vol. 2, pp. 129–135.
17.
Jiang
, L.
, Wong
, M.
, and Zohar
, Y.
, 2001
, “Forced Convection Boiling in a Microchannel Heat Sink
,” J. Microelectromech. Syst.
, 10
, pp. 80
–87
.18.
Peng
, X. F.
, and Wang
, B. X.
, 1993
, “Forced Convection and Flow Boiling Heat Transfer for Liquid Flowing through Microchannels
,” Int. J. Heat Mass Transfer
, 36
, pp. 3421
–3427
.19.
Ravigururajan
, T. S.
, 1998
, “Impact of Channel Geometry on Two-Phase Flow Heat Transfer Characteristics of Refrigerants in Microchannel Heat Exchangers
,” ASME J. Heat Transfer
, 120
, pp. 485
–491
.20.
Mudawar
, I.
, and Bowers
, M. B.
, 1999
, “Ultra-High Critical Heat Flux (CHF) for Subcooled Water Flow Boiling–I: CHF Data and Parametric Effects for Small Diameter Tubes
,” Int. J. Heat Mass Transfer
, 42
, pp. 1405
–1428
.21.
Hall
, D. D.
, and Mudawar
, I.
, 1999
, “Ultra-High Critical Heat Flux (CHF) for Subcooled Water Flow Boiling–II: High-CHF Database and Design Equations
,” Int. J. Heat Mass Transfer
, 42
, pp. 1429
–1456
.22.
Boure
, J. A.
, Bergles
, A. E.
, and Tong
, L. S.
, 1973
, “Review of Two-Phase Flow Instability
,” Nucl. Eng. Des.
, 25
, pp. 165
–192
.23.
Bergles, A. E., 1977, “Review of Instability in Two-Phase Systems,” Two-Phase Flows and Heat Transfer, S. Kakac, and F. Mayinger, eds., Hemisphere, Washington, Vol. 1, pp. 383–422.
24.
Yadigaroglu, G., 1981, “Two-phase Flow Instabilities and Propagation Phenomena,” Thermohydraulics of Two-Phase Systems for Industrial Design and Nuclear Engineering, J. M. Delhaye et al., eds., Hemisphere, Washington, pp. 353–403.
25.
Todreas, N. E., and Kazimi, M. S., 1990, Nuclear Systems I, Hemisphere, New York, Chap. 7.
26.
Shah, R. K., and London, A. L., 1978, Laminar Flow Forced Convection in Ducts: A Source Book for Compact Heat Exchanger Analytical Data, Supl. 1, Academic Press, New York, Chap. 7.
27.
Collier, J. G., and Thome, J. R., 1994, Convective Boiling and Condensation, 3rd edition, Oxford University Press, Oxford, Chap. 2.
28.
Martinelli
, R. C.
, and Nelson
, D. B.
, 1948
, “Prediction of Pressure Drop During Forced-Circulation Boiling of Water
,” Trans. ASME
, 70
, pp. 695
–702
.29.
Lockhart
, R. W.
, and Martinelli
, R. C.
, 1949
, “Proposed Correlation of Data for Isothermal Two-Phase, Two-Component Flow in Pipes
,” Chem. Eng. Process.
, 45
, pp. 39
–48
.30.
Chisholm, D., 1983, Two-Phase Flow in Pipelines and Heat Exchangers, Longman, New York, Chap. 7.
31.
Mukherjee
, S.
, and Mudawar
, I.
, “Pumpless Loop for Narrow Channel and Micro-Channel Boiling
,” ASME J. Electron. Packag.
, in press.32.
Qu, W., and Mudawar, I., 2002, “Thermal Design Methodology for High-Heat-Flux Single-Phase and Two-Phase Micro-Channel Heat Sinks,” Proceedings of the Eighth Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm 2002), C. H. Amon et al., eds., IEEE, pp. 347–359.
33.
Chen
, J. C.
, 1966
, “Correlation for Boiling Heat Transfer to Saturated Fluids in Convective Flow
,” I&EC Process Design and Development
, 5
, pp. 322
–329
.34.
Edelstein
, S.
, Perez
, A. J.
, and Chen
, J. C.
, 1984
, “Analytic Representation of Convective Boiling Functions
,” AIChE J.
, 30
, pp. 840
–841
.35.
Shah
, M. M.
, 1976
, “A New Correlation for Heat Transfer During Boiling Flow Through Pipes
,” ASHRAE Trans.
, 82
, pp. 66
–86
.36.
Shah
, M. M.
, 1982
, “Chart Correlation for saturated Boiling Heat Transfer: Equations and Further Study
,” ASHRAE Trans.
, 88
, pp. 185
–196
.37.
Kandlikar
, S. G.
, 1990
, “A general Correlation for Saturated Two-Phase Flow Boiling Heat Transfer insider Horizontal and Vertical Tubes
,” ASME J. Heat Transfer
, 112
, pp. 219
–228
.38.
Liu
, Z.
, and Winterton
, R. H. S.
, 1991
, “A General Correlation for Saturated and Subcooled Flow Boiling in Tubes and Annuli, based on a Nucleate Pool Boiling Equation
,” Int. J. Heat Mass Transfer
, 34
, pp. 2759
–2766
.39.
Steiner
, D.
, and Taborek
, J.
, 1992
, “Flow Boiling Heat transfer in Vertical Tubes Correlated by an Asymptotic Model
,” Heat Transfer Engineering
, 13
, pp. 43
–69
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