In the present paper, rectangular channels with six types of elliptic scale-roughened walls for heat transfer enhancement are numerically studied. Heat transfer and fluid flow characteristics for sixteen different scale-roughened models (with the scale height varying in the range from 1 mm to 2.5 mm) are numerically predicted using commercial computational fluid dynamics (CFD) code, Ansys cfx. The turbulent model employed is the k–ω based shear–stress transport (SST) model with automatic wall function treatment. In the performance evaluation, we use a “universal” porous media length scale based on volume averaging theory (VAT) to define the Reynolds number, Nusselt number, and friction factor. It is found that heat transfer performance is most favorable when the elliptic scales are oriented with their long axis perpendicular to the flow direction, while the scales elongated in the flow direction have lower Nusselt numbers and pressure drops compared with the circular scale-roughened channels. Results indicate that the scale-shaped roughness strongly spins the flow in the spanwise direction, which disrupts the near-wall boundary layers continuously and enhances the bulk flow mixing. With the flow marching in a more intense spiral pattern, a 40% improvement of heat transfer enhancement over the circular scale-roughened channels is observed.

Reference

1.
Ligrani
,
P. M.
,
Oliveira
,
M. M.
, and
Blaskovich
,
T.
,
2003
, “
Comparison of Heat Transfer Augmentation Techniques
,”
AIAA J.
,
41
(
3
), pp.
337
362
.10.2514/2.1964
2.
Taslim
,
M. E.
,
Li
,
T.
, and
Kercher
,
D. M.
,
1996
, “
Experimental Heat Transfer and Friction in Channels Roughened With Angled, V-Shaped, and Discrete Ribs on Two Opposite Walls
,”
Trans. ASME J. Turbomach.
,
118
(
1
), pp.
20
28
.10.1115/1.2836602
3.
Han
,
J. C.
,
Zhang
,
Y. M.
, and
Lee
,
C. P.
,
1991
, “
Augmented Heat Transfer in Square Channels With Parallel, Crossed, and V-Shaped Angled Ribs
,”
ASME J. Heat Transfer
,
113
(
3
), pp.
590
596
.10.1115/1.2910606
4.
Gao
,
X.
, and
Sunden
,
B.
,
2001
, “
Heat Transfer and Pressure Drop Measurements in Rib-Roughened Rectangular Ducts
,”
Exp. Therm. Fluid Sci.
,
24
(
1–2
), pp.
25
34
.10.1016/S0894-1777(00)00054-6
5.
Park
,
J. S.
,
Han
,
J. C.
,
Huang
,
Y.
,
Ou
,
S.
, and
Boyle
,
R. J.
,
1992
, “
Heat Transfer Performance Comparisons of Five Different Rectangular Channels With Parallel Angled Ribs
,”
Int. J. Heat Mass Transfer
,
35
(
11
), pp.
2891
2903
.10.1016/0017-9310(92)90309-G
6.
Cho
,
H. H.
,
Wu
,
S. J.
, and
Kwon
,
H. J.
,
2000
, “
Local Heat/Mass Transfer Measurements in a Rectangular Duct With Discrete Ribs
,”
ASME J. Turbomach.
,
122
(
3
), pp.
579
586
.10.1115/1.1303049
7.
Park
,
K.
,
Choi
,
D.-H.
, and
Lee
,
K.-S.
,
2004
, “
Optimum Design of Plate Heat Exchanger With Staggered Pin Arrays
,”
Numer. Heat Transfer
, Part A,
45
(
4
), pp.
347
361
.10.1080/10407780490250391
8.
Khan
,
W. A.
,
Culham
,
J. R.
, and
Yovanovich
,
M. M.
,
2006
, “
The Role of Fin Geometry in Heat Sink Performance
,”
ASME J. Electron. Packag.
,
128
(
4
), pp.
324
330
.10.1115/1.2351896
9.
Zhou
,
F.
, and
Catton
,
I.
,
2011
, “
Numerical Evaluation of Flow and Heat Transfer in Plate-Pin Fin Heat Sinks With Various Pin Cross-Sections
,”
Numer. Heat Transfer, Part A
,
60
(
2
), pp.
107
128
.10.1080/10407782.2011.588574
10.
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. Turbomach.
,
123
(
1
), pp.
115
123
.10.1115/1.1333694
11.
Mahmood
,
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
,
45
(
10
), pp.
2011
2020
.10.1016/S0017-9310(01)00314-3
12.
Burgess
,
N. K.
, and
Ligrani
,
P. M.
,
2005
, “
Effects of Dimple Depth on Channel Nusselt Numbers and Friction Factors
,”
ASME J. Heat Transfer
,
127
(
8
), pp.
839
847
.10.1115/1.1994880
13.
Mahmood
,
G. I.
,
Sabbagh
,
M. Z.
, and
Ligrani
,
P. M.
,
2001
, “
Heat Transfer in a Channel With Dimples and Protrusions on Opposite Walls
,”
J. Thermophys. Heat Transfer
,
15
(
3
), pp.
275
283
.10.2514/2.6623
14.
Chang
,
S. W.
,
Liou
,
T.-M.
, and
Lu
,
M. H.
,
2005
, “
Heat Transfer of Rectangular Narrow Channel With Two Opposite Scale-Roughened Walls
,”
Int. J. Heat Mass Transfer
,
48
(
19–20
), pp.
3921
3931
.10.1016/j.ijheatmasstransfer.2005.04.015
15.
Chang
,
S. W.
,
Liou
,
T. M.
,
Chiang
,
K. F.
, and
Hong
,
G. F.
,
2008
, “
Heat Transfer and Pressure Drop in Rectangular Channel With Compound Roughness of V-Shaped Ribs and Deepened Scales
,”
Int. J. Heat Mass Transfer
,
51
(
3–4
), pp.
457
468
.10.1016/j.ijheatmasstransfer.2007.05.010
16.
Chang
,
S. W.
,
Yang
,
T. L.
,
Liou
,
T.-M.
, and
Fang
,
H. G.
,
2009
, “
Heat Transfer in Rotating Scale-Roughened Trapezoidal Duct at High Rotation Numbers
,”
Appl. Therm. Eng.
,
29
(
8–9
), pp.
1682
1693
.10.1016/j.applthermaleng.2008.07.024
17.
Chang
,
S. W.
,
Yang
,
T. L.
,
Liou
,
T.-M.
, and
Hong
,
G. F.
,
2009
, “
Heat Transfer of Rotating Rectangular Duct With Compound Scaled Roughness and V-Ribs at High Rotation Numbers
,”
Int. J. Therm. Sci.
,
48
(
1
), pp.
174
187
.10.1016/j.ijthermalsci.2008.03.001
18.
Chang
,
S. W.
, and
Lees
,
A. W.
,
2010
, “
Endwall Heat Transfer and Pressure Drop in Scale-Roughened Pin-Fin Channels
,”
Int. J. Therm. Sci.
,
49
(
4
), pp.
702
713
.10.1016/j.ijthermalsci.2009.09.008
19.
Zhou
,
F.
,
DeMoulin
,
G. W.
,
Geb
,
D. J.
, and
Catton
,
I.
,
2012
, “
Closure for a Plane Fin Heat Sink With Scale-Roughened Surfaces for Volume Averaging Theory (VAT) Based Modeling
,”
Int. J. Heat Mass Transfer
,
55
(
25–26
), pp.
7677
7685
.10.1016/j.ijheatmasstransfer.2012.07.075
20.
Bardina
,
J. E.
,
Huang
,
P. G.
, and
Coakley
,
T. J.
,
1997
, “
Turbulence Modeling Validation, Testing, and Development
,” NASA Technical Memorandum.
21.
Menter
,
F. R.
,
1994
, “
Two-Equation Eddy-Viscosity Turbulence Models for Engineering Applications
,”
AIAA J.
,
32
(
8
), pp.
1598
1605
.10.2514/3.12149
22.
Menter
,
F. R.
,
Kuntz
,
M.
, and
Langtry
,
R.
,
2003
, “
Ten Years of Industrial Experience With the SST Turbulence Model
,”
Turbul. Heat Mass Transfer
,
4
, pp.
625
632
.
23.
Wee
,
H.
,
Zhang
,
Q.
,
Ligrani
,
P. M.
, and
Narasimhan
,
S.
,
2008
, “
Numerical Predictions of Heat Transfer and Flow Characteristics of Heat Sinks With Ribbed and Dimpled Surfaces in Laminar Flow
,”
Numer. Heat Transfer, Part A
,
53
(
11
), pp.
1156
1175
.10.1080/10407780701853371
24.
Travkin
,
V. S.
, and
Catton
,
I.
,
2001
, “
Transport Phenomena in Heterogeneous Media Based on Volume Averaging Theory
,”
Adv. Heat Transfer
,
34
, pp.
1
144
.10.1016/S0065-2717(01)80011-3
25.
Whitaker
,
S.
,
1972
, “
Forced Convection Heat Transfer Correlations for Flow in Pipes, Past Flat Plates, Single Cylinders, Single Spheres, and for Flow in Packed Beds and Tube Bundles
,”
AIChE J.
,
18
(
2
), pp.
361
371
.10.1002/aic.690180219
26.
Zhou
,
F.
,
Hansen
,
N. E.
,
Geb
,
D. J.
, and
Catton
,
I.
,
2011
, “
Obtaining Closure for Fin-and-Tube Heat Exchanger Modeling Based on Volume Averaging Theory (VAT)
,”
ASME J. Heat Transfer
,
133
(
11
), p.
111802
.10.1115/1.4004393
27.
Catton
,
I.
,
2011
, “
Conjugate Heat Transfer Within a Heterogeneous Hierarchical Structure
,”
ASME J. Heat Transfer
,
133
(
10
), p.
103001
.10.1115/1.4003576
28.
Geb
,
D.
,
Zhou
,
F.
, and
Catton
,
I.
,
2012
, “
Internal Heat Transfer Coefficient Determination in a Packed Bed From the Transient Response Due to Solid Phase Induction Heating
,”
ASME J. Heat Transfer
,
134
(
4
), p.
042604
.10.1115/1.4005098
29.
Zhou
,
F.
,
Hansen
,
N. E.
,
Geb
,
D. J.
, and
Catton
,
I.
,
2011
, “
Determination of the Number of Tube Rows to Obtain Closure for Volume Averaging Theory Based Model of Fin-and-Tube Heat Exchangers
,”
ASME J. Heat Transfer
,
133
(
12
), p.
121801
.10.1115/1.4004478
30.
Zhou
,
F.
, and
Catton
,
I.
,
2012
, “
Volume Averaging Theory (VAT) Based Modeling and Closure Evaluation for Fin-and-Tube Heat Exchangers
,”
Heat Mass Transfer
,
48
(
10
), pp.
1813
1823
.10.1007/s00231-012-1025-7
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