An experimental and numerical study was conducted to investigate the flow and heat transfer characteristics in channels with pin fin-dimple combined arrays of different configurations, where dimples are located transversely or both transversely and streamwisely between the pin fins. The flow structure, friction factor, and heat transfer characteristics of the pin fin-dimple channels of different configurations have been obtained and compared with each other for the Reynolds number range of 8200–50,500. The experimental study showed that, compared to the pin fin channel, depending on the configurations of the pin fin-dimple combined arrays the pin fin-dimple channel can have distinctively further improved convective heat transfer performance by 8.0%–20.0%, whereas lower or slightly higher friction factors over the studied Reynolds number range. Furthermore, three-dimensional and steady-state conjugate computations have been carried out for similar experimental conditions. The numerical computations showed detailed characteristics of the distribution of the velocity and turbulence level in the flow, which revealed the underlying mechanisms for the pressure loss and heat transfer characteristics in the pin fin-dimple channels of different configurations.

References

1.
Han
,
J. C.
,
Dutta
,
S.
, and
Ekkad
,
S.
,
2001
,
Gas Turbine Heat Transfer and Cooling Technology
,
Taylor & Francis
,
London
.
2.
Han
,
J. C.
,
2006
, “
Turbine Blade Cooling Studies at Texas A&M University: 1980–2004
,”
AIAA J. Thermophys. Heat Transfer
,
20
,
pp.
161
187
.10.2514/1.15403
3.
VanFossen
,
G. J.
,
1982
, “
Heat Transfer Coefficients for Staggered Arrays of Short Pin Fins
,”
ASME J. Eng. Power
,
104
,
pp.
268
274
.10.1115/1.3227275
4.
Metzger
,
D. E.
,
Berry
,
R. A.
, and
Bronson
,
J. P.
,
1982
, “
Developing Heat Transfer in Rectangular Ducts With Staggered Arrays of Short Pin Fins
,”
ASME J. Heat Transfer
,
104
,
pp.
700
706
.10.1115/1.3245188
5.
Metzger
,
D. E.
,
Fan
,
Z. X.
, and
Shepard
,
W. B.
,
1982
, “
Pressure Loss and Heat Transfer Through Multiple Rows of Short Pin Fins
,”
Heat Transfer
,
Vol.
3
,
U.
Grigull
, ed.,
Hemisphere
,
Washington, DC
,
pp.
137
142
.
6.
Metzger
,
D. E.
,
Shepard
,
W. B.
, and
Haley
,
S. W.
,
1986
, “
Row Resolved Heat Transfer Variations in Pin Fin Arrays Including Effects of Non-Uniform Arrays and Flow Convergence
,”
ASME Paper No. 86-GT-132
.
7.
Chyu
,
M. K.
,
1990
, “
Heat Transfer and Pressure Drop for Short Pin-Fin Arrays With Pin-Endwall Fillet
,”
ASME J. Heat Transfer
,
112
,
pp.
926
932
.10.1115/1.2910502
8.
Chyu
,
M. K.
,
Hsing
,
Y. C.
,
Shih
,
T. I. P.
, and
Natarajan
,
V.
,
1999
, “
Heat Transfer Contributions of Pins and Endwall in Pin-Fin Arrays: Effects of Thermal Boundary Condition Modeling
,”
ASME J. Turbom.
,
121
,
pp.
257
263
.10.1115/1.2841309
9.
Lau
,
S. C.
,
Han
,
J. C.
, and
Kim
,
Y. S.
,
1989
, “
Turbulent Heat Transfer and Friction in Pin Fin Channels With Lateral Flow Ejection
,”
ASME J. Heat Transfer
,
111
,
pp.
51
58
.10.1115/1.3250657
10.
McMillin
,
R. D.
, and
Lau
,
S. C.
,
1994
, “
Effects of Trailing-Edge Ejection on Local Heat (Mass) Transfer in Pin Fin Cooling Channels in Turbine Blades
,”
ASME J. Turbom.
,
116
,
pp.
159
168
.10.1115/1.2928271
11.
Won
,
S. Y.
,
Mahmood
,
G. I.
, and
Ligrani
,
P. M.
,
2004
, “
Spatially-Resolved Heat Transfer and Flow Structure in a Rectangular Channel With Pin Fins
,”
Int. J. Heat Mass Transfer
,
47
,
pp.
1731
1743
.10.1016/j.ijheatmasstransfer.2003.10.007
12.
Ames
,
F. E.
,
Dvorak
,
L. A.
, and
Morrow
,
M. J.
,
2005
, “
Turbulent Augmentation of Internal Convection Over Pins in Staggered-Pin Fin Arrays
,”
ASME J. Turbom.
,
127
,
pp.
183
190
.10.1115/1.1811090
13.
Lyall
,
M. E.
,
Thrift
,
A. A.
,
Thole
,
K. A.
,
Kohli
,
A.
,
2011
, “
Heat Transfer From Low Aspect Ratio Pin Fins
,”
ASME J. Turbom.
,
133
, p.
011001
.10.1115/1.2812951
14.
Ligrani
,
P. M.
,
Oliveira
,
M. M.
, and
Blaskovich
,
T.
,
2003
, “
Comparison of Heat Transfer Augmentation Techniques
,”
AIAA J.
,
41
,
pp.
337
362
.10.2514/2.1964
15.
Afanasyev
,
V. N.
,
Chudnovsky
,
Ya., P.
,
Leontiev
,
A. I.
, and
Roganov
,
P. S.
,
1993
, “
Turbulent Flow Friction and Heat Transfer Characteristics for Spherical Cavities on a Flat Plate
,”
Exp. Therm. Fluid Sci.
,
7
,
pp.
1
8
.10.1016/0894-1777(93)90075-T
16.
Terekhov
,
V. I.
,
Kalinina
,
S. V.
, and
Mshvidobadze
,
Y. M.
,
1997
, “
Heat Transfer Coefficient and Aerodynamic Resistance on a Surface With a Single Dimple
,”
J. Enhanced Heat Transfer
,
4
,
pp.
131
145
.
17.
Chyu
,
M. K.
,
Yu
,
Y.
,
Ding
,
H.
,
Downs
,
J. P.
, and
Soechting
,
F. O.
,
1997
, “
Concavity Enhanced Heat Transfer in an Internal Cooling Passage
,”
ASME Paper No. 97-GT-437
.
18.
Moon
,
H. K.
,
O'Connell
,
T.
, and
Gletzer
,
B.
,
2000
, “
Channel Height Effect on Heat Transfer and Friction in a Dimpled Passage
,”
ASME J. Eng. Gas Turbine Power
,
122
,
pp.
307
313
.10.1115/1.483208
19.
Mahmood
,
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. Turbom.
,
123
,
pp.
115
123
.10.1115/1.1333694
20.
Ligrani
,
P. M.
,
Harrison
,
J. L.
,
Mahmood
,
G. I.
, and
Hill
,
M. L.
,
2001
, “
Flow Structure Due to Dimple Depression on a Channel Surface
,”
Phys. Fluids
,
13
,
pp.
3442
3451
.10.1063/1.1404139
21.
Burgess
,
N. K.
, and
Ligrani
,
P. M.
,
2005
, “
Effects of Dimple Depth on Channel Nusselt Numbers and Friction Factors
,”
ASME J. Heat Transfer
,
127
,
pp.
839
847
.10.1115/1.1994880
22.
Rao
,
Y.
,
Wan
,
C. Y.
,
Xu
,
Y. M.
, and
Zang
,
S. S.
,
2011
, “
Spatially-Resolved Heat Transfer Characteristics in Channels With Pin Fin and Pin Fin-Dimple Arrays
,”
Int. J. Therm. Sci.
,
50
,
pp.
2277
2289
.
23.
Bunker
,
R. S.
,
Bailey
,
J. C.
, and
Lee
,
C. P.
, “
Hot Gas Path Component With Mesh and Dimpled Cooling
,” U.S. Patent No. 20050106021A1.
24.
FLUENT 6.3 Help Document
,
Fluent, Inc.
,
2006
.
25.
Kays
,
W.
,
Crawford
,
M.
, and
Weigand
,
B.
,
2005
,
Convective Heat and Mass Transfer
, 4th ed.,
McGraw-Hill, Inc.
,
New York
.
26.
Park
,
J.
,
Desam
,
P. R.
, and
Ligrani
,
P. M.
,
2004
, “
Numerical Predictions of Flow Structure Above a Dimpled Structure in a Channel
,”
Numer. Heat Transfer, Part A
,
45
,
pp.
1
20
.10.1080/1040778049026740
27.
Xie
,
G.
,
Sunden
,
B.
, and
Zhang
,
W.
,
2011
, “
Comparisons of Pins/Dimples/Protrusions Cooling Concepts for a Turbine Blade Tip-Wall at High Reynolds Numbers
,”
ASME J. Heat Transfer
,
133
, p.
061902
.10.1115/1.4003558
28.
Kline
,
S. J.
, and
McClintock
,
F. A.
,
1953
, “
Describing Uncertainties in Single-Sample Experiments
,”
Mech. Eng.
,
75
,
pp.
3
8
.
29.
Rao
,
Y.
,
Wan
,
C. Y.
, and
Zang
,
S. S.
,
2010
, “
Comparisons of Flow Friction and Heat Transfer Performance in Rectangular Channels With Pin Fin-Dimple, Pin Fin and Dimple Arrays
,”
ASME Paper No. GT2010-22442
.
30.
Gee
,
D. L.
, and
Webb
,
R. L.
,
1980
, “
Forced Convection Heat Transfer in Helically Rib-Roughened Tubes
,”
Int. J. Heat Mass Transfer
,
23
,
pp.
1127
1136
.10.1016/0017-9310(80)90177-5
You do not currently have access to this content.