The effect of the dimple shape and orientation on the heat transfer coefficient of a vertical fin surface was determined both numerically and experimentally. The investigation focused on the laminar channel flow between fins, with a and 1000. Numerical simulations were performed using a commercial computational fluid dynamics code to analyze optimum configurations, and then an experimental investigation was conducted on flat and dimpled surfaces for comparison purposes. Numerical results indicated that oval dimples with their “long” axis oriented perpendicular to the direction of the flow offered the best thermal improvement, hence the overall Nusselt number increased up to 10.6% for the dimpled surface. Experimental work confirmed these results with a wall-averaged temperature reduction of up to , which depended on the heat load and the Reynolds number. Pressure losses due to the dimple patterning were also briefly explored numerically in this work.
Issue Section:
Forced Convection
1.
Silva
, C.
, Marotta
, E.
, and Fletcher
, L.
, 2007, “Flow Structure and Enhanced Heat Transfer in Channel Flow With Dimpled Surfaces: Application to Heat Sinks in Microelectronic Cooling
,” ASME J. Electron. Packag.
1043-7398, 129
, pp. 157
–166
.2.
Chyum
, M. K.
, Yu
, Y.
, Ding
, H.
, Downs
, J. P.
, and Soechting
, F. O.
, 1997, “Concavity Enhancement Heat Transfer in an Internal Cooling Passage
,” ASME Paper No. 97-GT-437.3.
Moon
, H. K.
, O’Connel
, T.
, and Glezer
, B.
, 2000, “Channel Height Effect on Heat Transfer and Friction in a Dimple Passage
,” ASME J. Eng. Gas Turbines Power
0742-4795, 122
, pp. 307
–313
.4.
Mamood
, G. I.
, Hill
, M. L.
, Nelson
, D. L.
, Ligrani
, P. M.
, Moon
, H. K.
, and Glezer
, B.
, 2001, “Local Heat Transfer and Flow Structure on and Above a Dimpled Surface in a Channel
,” ASME J. Turbomach.
0889-504X, 123
, pp. 115
–123
.5.
Mamood
, G. I.
, and Ligrani
, P. M.
, 2002, “Heat Transfer in a Dimpled Channel: Combined Influences of Aspect Ratio, Temperature Ratio, Reynolds Number and Flow Structure
,” Int. J. Heat Mass Transfer
0017-9310, 45
, pp. 2011
–2020
.6.
Mamood
, G. I.
, Sabbagh
, M. Z.
, and Ligrani
, P. M.
, 2001, “Heat Transfer in a Channel With Dimples and Protrusion on Opposite Walls
,” J. Thermophys. Heat Transfer
0887-8722, 15
(3
), pp. 275
–283
.7.
Burguess
, N. K.
, Oliveira
, M. M.
, and Ligrani
, P. M.
, 2002, “Nusselt Number Behavior on Deep Dimpled Surfaces Within a Channel
,” ASME Paper No. IMECE 2002–32941.8.
Ligrani
, P. M.
, Mahmood
, G. I.
, Harrison
, J. L.
, Clayton
, C. M.
, and Nelson
, D. L.
, 2001, “Flow Structure and Local Nusselt Number Variation in a Channel With Dimples and Protrusions on Opposite Walls
,” Int. J. Heat Mass Transfer
0017-9310, 44
, pp. 4413
–4425
.9.
Won
, S. Y.
, Zhang
, Q.
, and Ligrani
, P. M.
, 2005, “Comparisons of Flow Structure Above Dimpled Surfaces With Different Dimple Depths in a Channel
,” Phys. Fluids
1070-6631, 17
, p. 045105
.10.
Burgess
, N. K.
, and Ligrani
, P. M.
, 2005, “Effects of Dimple Depth on Channel Nusselt Numbers and Friction Factors
,” ASME J. Heat Transfer
0022-1481, 127
, pp. 839
–847
.11.
Ligrani
, P. M.
, Burgess
, N. K.
, and Won
, S. Y.
, 2005, “Nusselt Numbers and Flow Structure on and Above a Shallow Dimpled Surface Within a Channel Including Effects of Inlet Turbulence Intensity Level
,” ASME J. Turbomach.
0889-504X, 127
, pp. 321
–330
.12.
Bunker
, R. S.
, and Donellan
, K. F.
, 2002, “Heat Transfer and Friction Factors for Flow Inside Circular Tubes With Concavity Surfaces
,” ASME Paper No. GT 2003-38053.13.
Syred
, N.
, Khalatov
, A.
, Kozlov
, A.
, Shchukin
, A.
, and Agachev
, R.
, 2000, “Effects of Surface Curvature on Heat Transfer and Hydrodynamics Within a Single Hemispherical Dimple
,” ASME Paper No. 2000-GT-236.14.
Han
, J.
, 2006, “Turbine Blade Cooling Studies at Texas A&M University: 1980–2004
,” J. Thermophys. Heat Transfer
0887-8722, 20
(2
), pp. 161
–187
.15.
Chang
, S. W.
, Jan
, Y. J.
, and Chang
, S. F.
, 2006, “Heat Transfer of Impinging Jet-Array Over Convex-Dimpled Surface
,” Int. J. Heat Mass Transfer
0017-9310, 49
, pp. 3045
–3059
.16.
Small
, E.
, Sadeghipour
, S. M.
, and Asheghi
, M.
, 2006, “Heat Sinks With Enhanced Heat Transfer Capability for Electronic Cooling Applications
,” ASME J. Electron. Packag.
1043-7398, 128
, pp. 285
–290
.17.
Wei
, X. J.
, Joshi
, Y. K.
, and Ligrani
, P. M.
, 2007, “Numerical Simulation of Laminar Flow and Heat Transfer Inside a Micro-Channel With One Dimpled Wall
,” ASME J. Electron. Packag.
1043-7398, 129
, pp. 63
–70
.18.
Isaev
, S. A.
, Leontiev
, A. I.
, Usachev
, A. E.
, and Frolov
, D. P.
, 1997, “Numerical Simulation of Laminar Incompressible Three-Dimensional Flow Around a Dimple (Vortex Dynamics and Heat Transfer)
,” Russian Ministry of Science and Technology Institute for High-Performance Computing and Databases, preprint 6-67.19.
Isaev
, S. A.
, Leontiev
, A. I.
, Metov
, Kh. T.
, and Kharchenko
, V. B.
, 2002, “Modeling of the Influence of Viscosity on the Tornado Heat Exchange in Turbulent Flow Around a Small Hole on the Plane
,” J. Eng. Phys. Thermophys.
1062-0125, 75
(4
), pp. 890
–898
.20.
Isaev
, S. A.
, Leontiev
, A. I.
, Metov
, Kh. T.
, and Kharchenko
, V. B.
, 2002, “Verification of the Multiblock Computational Technology in Calculating Laminar and Turbulent Flow Around a Spherical Hole on a Channel Wall
,” J. Eng. Phys. Thermophys.
1062-0125, 75
(5
), pp. 1155
–1158
.21.
Isaev
, S. A.
, and Leontiev
, A. I.
, 2003, “Numerical Simulation of Vortex Enhancement of Heat Transfer Under Conditions of Turbulent Flow Past a Spherical Dimple on the Wall of a Narrow Channel
,” High Temp.
0018-151X, 41
(5
), pp. 665
–679
.22.
Isaev
, S. A.
, Leontiev
, A. I.
, Baranov
, P. A.
, Metov
, Kh. T.
, and Usachev
, A. E.
, 2001, “Numerical Analysis of the Effect of Viscosity on the Vortex Dynamics in Laminar Separated Flow Past a Dimple on a Plane With Allowance for its Asymmetry
,” J. Eng. Phys. Thermophys.
1062-0125, 74
(2
), pp. 339
–346
.23.
Isaev
, S. A.
, Leontiev
, A. I.
, and Baranov
, P. A.
, 2000, “Identification of Self-Organized Vortex-Like Structures in Numerically Simulated Turbulent Flow of a Viscous Incompressible Liquid Streaming Around a Well on a Plane
,” Tech. Phys. Lett.
1063-7850, 26
(1
), pp. 15
–18
.24.
Park
, J.
, Desam
, P. R.
, and Ligrani
, P. M.
, 2004, “Numerical Predictions of Flow Structure Above a Dimpled Surface in a Channel
,” Numer. Heat Transfer, Part A
1040-7782, 45
, pp. 1
–20
.25.
Park
, J.
, and Ligrani
, P. M.
, 2005, “Numerical Predictions of Heat Transfer and Fluid Flow Characteristics for Seven Different Dimpled Surfaces in a Channel
,” Numer. Heat Transfer, Part A
1040-7782, 47
, pp. 209
–232
.26.
Kin
, K. Y.
, and Choi
, J. Y.
, 2005, “Shape Optimization of a Dimpled Channel to Enhance Turbulent Heat Transfer
,” Numer. Heat Transfer, Part A
1040-7782, 48
, pp. 901
–915
.27.
Kline
, S. J.
, and McClintock
, F. A.
, 1953, “Describing Uncertainties in Single Sample Experiments
,” Mech. Eng. (Am. Soc. Mech. Eng.)
0025-6501, 75
, pp. 3
–8
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