The purpose of this paper is to demonstrate the possibility to selectively tune the convective heat transfer coefficient in different sections of a heat sink by varying the density of microfeatures in order to minimize temperature gradients between discrete heat sources positioned along the flow path. Lifetime of power electronics is strongly correlated to the thermal management of the junction. Therefore, it is of interest to have constant junction temperatures across all devices in the array. Implementation of microfeature enhancement on the convective side improves the heat transfer due to an increase in surface area. Specific shapes such as micro-hydrofoils offer a reduced pressure drop allowing for combined improvement of heat transfer and flow performance. This study presents experimental results from an array of three discrete heat sources (20 × 15 mm) generating 100 W/cm2 and positioned in line along the flow path with a spacing of 10 mm between each of the sources. The heat sink was machined out of aluminum 6061, and micro-hydrofoils with a characteristic length of 500 μm were embedded in the cold plate. The cooling medium used is water at a flow rate of 3.6–13.4 g/s corresponding to a Reynolds number of 420–1575. It is demonstrated that the baseplate temperature can be maintained below 90 °C, and the difference between the maximum temperatures of each heat source is less than 6.7 °C at a heat flux of 100 W/cm2 and a water flow rate of 4.8 g/s.

References

References
1.
Thome
,
J.
,
2004
, “
Boiling in Microchannels: A Review of Experiment and Theory
,”
Int. J. Heat Fluid Flow
,
25
(
2
), pp.
128
139
.
2.
Thome
,
J.
,
2006
, “
State-of-the-Art Overview of Boiling and Two-Phase Flows in Microchannels
,”
Heat Transfer Eng.
,
27
(
9
), pp.
4
19
.
3.
Thome
,
J.
, and
Consolini
,
L.
,
2010
, “
Mechanisms of Boiling in Microchannels: Critical Assessment
,”
Heat Trans. Eng.
,
31
(
4
), pp.
288
297
.
4.
Kandlikar
,
S.
,
2004
, “
Heat Transfer Mechanisms During Flow Boiling in Microchannels
,”
ASME J. Heat Transfer
,
126
(
1
), pp.
8
16
.
5.
Kandlikar
,
S.
,
2002
, “
Fundamental Issues Related to Flow Boiling in Minichannels and Microchannels
,”
Exp. Therm. Fluid Sci.
,
26
, pp.
389
407
.
6.
Kandlikar
,
S.
, and
Grande
,
W.
,
2003
, “
Evolution of Microchannel Flow Passages—Thermohydraulic Performance and Fabrication Technology
,”
Heat Transfer Eng.
,
24
(
1
), pp.
3
17
.
7.
Tuckerman
,
D. B.
, and
Pease
,
R. F. W.
,
1981
, “
High-Performance Heat Sinking for VLSI
,”
IEEE Electr. Dev. Lett.
,
2
(
5
), pp.
126
129
.
8.
Mehendale
,
S. S.
,
Jacobi
,
A. M.
, and
Shah
,
R. K.
,
2000
, “
Fluid Flow and Heat Transfer at Micro- and Meso-Scales With Application to Heat Exchanger Design
,”
ASME Appl. Mech. Rev.
,
53
(
7
), pp.
175
193
.
9.
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
(
12
), pp.
2549
2565
.
10.
Sobhan
,
C. B.
, and
Garimella
,
S. V.
,
2001
, “
A Comparative Analysis of Studies on Heat Transfer and Fluid Flow in Microchannels
,”
Microscale Thermophys. Eng.
,
5
(
4
), pp.
293
311
.
11.
García-Hernando
,
N.
,
Acosta-Iborra
,
A.
,
Ruiz-Rivas
,
U.
, and
Izquierdo
,
M.
,
2009
, “
Experimental Investigation of Fluid Flow and Heat Transfer in a Single-Phase Liquid Flow Micro-Heat Exchanger
,”
Int. J. Heat Mass Transfer
,
52
, pp.
5433
5446
.
12.
Peles
,
Y.
,
Kosar
,
A.
,
Mishra
,
C.
,
Chih-Jung
,
K.
, and
Schneider
,
B.
,
2005
, “
Forced Convective Heat Transfer Across a Pin Fin Micro Heat Sink
,”
Int. J. Heat Mass Transfer
,
48
(
17
), pp.
3615
3627
.
13.
Kosar
,
A.
, and
Peles
,
Y.
,
2006
, “
Thermal–Hydraulic Performance of MEMS-Based Pin Fin Heat Sink
,”
ASME J. Heat Transfer
,
128
(
2
), pp.
121
131
.
14.
Abdel-Rehim
,
Z. S.
,
2009
, “
Optimization and Thermal Performance Assessment of Pin-Fin Heat Sinks
,”
Energy Sources
,
31
, pp.
51
65
.
15.
Brunschwiler
,
T.
,
Michel
,
B.
,
Rothuizen
,
H.
,
Kloter
,
U.
,
Wunderle
,
B.
,
Oppermann
,
H.
, and
Reichl
,
H.
,
2008
, “
Interlayer Cooling Potential in Vertically Integrated Packages
,”
Microsyst. Technol.
,
15
(1), pp.
57
74
.
16.
Deshmukh
,
P. A.
, and
Warkhedkar
,
R. M.
,
2013
, “
Thermal Performance of Elliptical Pin Fin Heat Sink Under Combined Natural and Forced Convection
,”
Exp. Therm. Fluid Sci.
,
50
, pp.
61
68
.
17.
Hansen
,
N.
,
Catton
,
I.
, and
Zhou
,
F.
,
2010
, “
Heat Sink Optimization: A Multi-Parameter Optimization Problem
,”
ASME
Paper No. IHTC14-22968.
18.
Khan
,
W. A.
,
Culham
,
J. R.
, and
Yovanovich
,
M. M.
,
2008
, “
Optimization of Pin-Fin Heat Sinks in Bypass Flow Using Entropy Generation Minimization Method
,”
ASME J. Electron. Packag.
,
130
(
3
), p.
031010
.
19.
Mitre
,
J. F.
,
Santana
,
L. M.
,
Damian
,
R. B.
,
Su
,
J.
, and
Lage
,
P. L. C.
,
2010
, “
Numerical Study of Turbulent Heat Transfer in 3D Pin-Fin Channels: Validation of a Quick Procedure to Estimate Mean Values in Quasi-Periodic Flows
,”
Appl. Therm. Eng.
,
30
, pp.
2796
2803
.
20.
Ndao
,
S.
,
Peles
,
Y.
, and
Jensen
,
M. K.
,
2009
, “
Multi-Objective Thermal Design Optimization and Comparative Analysis of Electronics Cooling Technologies
,”
Int. J. Heat Mass Transfer
,
52
, pp.
4317
4326
.
21.
Shafeie
,
H.
,
Abouali
,
O.
,
Jafarpur
,
K.
, and
Ahmadi
,
G.
,
2013
, “
Numerical Study of Heat Transfer Performance of Single-Phase Heat Sinks With Micro Pin-Fin Structures
,”
Appl. Therm. Eng.
,
58
, pp.
68
76
.
22.
Chyu
,
M. K.
,
Hsing
,
Y. C.
, and
Natarajan
,
V.
,
1998
, “
Convective Heat Transfer of Cubic Fin Arrays in a Narrow Channel
,”
ASME J. Turbomach.
,
120
(
2
), pp.
362
367
.
23.
Kosar
,
A.
,
Mishra
,
C.
, and
Peles
,
Y.
,
2005
, “
Laminar Flow Across a Bank of Low Aspect Ratio Micro Pin Fins
,”
ASME J. Fluids Eng.
,
127
(
3
), pp.
419
430
.
24.
Prasher
,
R. S.
,
Dirner
,
J.
,
Chang
,
J. Y.
,
Myers
,
A.
,
Chau
,
D.
,
He
,
D.
, and
Prstic
,
S.
,
2007
, “
Nusselt Number and Friction Factor of Staggered Arrays of Low Aspect Ratio Micropin-Fins Under Cross Flow for Water as Fluid
,”
ASME J. Heat Transfer
,
129
(
2
), pp.
141
153
.
25.
John
,
T. J.
,
Mathew
,
B.
, and
Hegab
,
H.
,
2010
, “
Characteristic Study on the Optimization of Micro Pin-Fin Heat Sink With Staggered Arrangement
,”
10th AIAA/ASME Joint Thermophysics and Heat Transfer Conference
, Chicago, IL, June 28–July 1,
AIAA
Paper No. 2010-4781.
26.
Kosar
,
A.
,
2008
, “
Two-Phase Pressure Drop Across a Hydrofoil-Based Micro Pin Device Using R-123
,”
Exp. Therm. Fluid Sci.
,
32
(
6
), pp.
1213
1221
.
27.
Kosar
,
A.
, and
Peles
,
Y.
,
2007
, “
Boiling Heat Transfer in A Hydrofoil-Based Micro Pin Fin Heat Sink
,”
Int. J. Heat Mass Transfer
,
50
, pp.
1018
1034
.
28.
Semidey
,
S. A.
,
2012
, “
Thermal Design and Optimization of High Torque Density Electric Machines
,” Ph.D. thesis, Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA.
29.
Semidey
,
S. A.
, and
Mayor
,
J. R.
,
2014
, “
Empirical Investigation of Aligned Micro-Hydrofoils Arrays Under Single-Phase Cross Flow: Part 1. Nusselt Number Correlation
,”
ASME 2014 International Mechanical Engineering Congress and Exposition
,
Montreal
,
Canada
, Nov. 14–20.
30.
Semidey
,
S. A.
, and
Mayor
,
J. R.
,
2014
, “
Empirical Investigation of Aligned Micro-Hydrofoils Arrays Under Single-Phase Cross Flow: Part 2. Friction Factor Correlation
,”
ASME 2014 International Mechanical Engineering Congress and Exposition
,
Montreal
,
Canada
, Nov. 14–20.
31.
Žukauskas
,
A.
,
1972
, “
Heat Transfer From Tubes in Crossflow
,”
Adv. Heat Transfer
,
8
, pp.
93
160
.
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