The flow structures behind bare and aluminum foam-covered single circular cylinders were investigated using particle image velocimetry (PIV). The experiments are conducted for a range of Reynolds numbers from 2000 to 8000, based on the outer cylinders diameter and the air velocity upstream of the cylinder. The analysis of the PIV data shows the important effects of the foam cover and the inlet velocity on the separated structures. The results show a considerable increase in the wake size behind a foam-covered cylinder compared to that of a bare cylinder. Furthermore, the turbulence intensity is found to be around 10% higher in the case of the foam-covered cylinder where the wake size is approximately doubled for the former case compared to the latter. The turbulence kinetic energy, however, is found to be less Reynolds dependent in the case of the foam-covered cylinder. In addition, small scale structures contribute to the formation of the flow structures in the foam-covered cylinder making them a more efficient turbulent generator for the next rows when used in a heat exchanger tube bundle. On the other hand, a higher energy level in such separated structures will translate into increased pressure drop compared to bare cylinders. Finally, the results of this study can be used as an accurate set of boundary conditions for modeling the flow field past such cylinders.

References

References
1.
Odabaee
,
M.
,
Hooman
,
K.
, and
Gurgenci
,
H.
,
2011
, “
Metal Foam Heat Exchangers for Heat Transfer Augmentation From a Cylinder in Cross-Flow
,”
Transport Porous Media
,
86
(
3
), pp.
911
923
.10.1007/s11242-010-9664-y
2.
Mahjoob
,
S.
, and
Vafai
,
K.
,
2008
, “
A Synthesis of Fluid and Thermal Transport Models for Metal Foam Heat Exchangers
,”
Int. J. Heat Mass Transfer
,
51
(
15
), pp.
3701
3711
.10.1016/j.ijheatmasstransfer.2007.12.012
3.
Bhattacharyya
,
S.
, and
Singh
,
A.
,
2009
, “
Augmentation of Heat Transfer From a Solid Cylinder Wrapped With a Porous Layer
,”
Int. J. Heat Mass Transfer
,
52
(
7
), pp.
1991
2001
.10.1016/j.ijheatmasstransfer.2008.08.041
4.
Ashtiani Abdi
,
I.
,
Khashehchi
,
M.
, and
Hooman
,
K.
,
2012
, “
PIV Analysis of the Wake Behind a Single Tube and a One-Row Tube Bundle: Foamed and Finned Tubes
,” Proceedings of the 18th Australasian Fluid Mechanics Conference, Australasian Fluid Mechanics Society, Launceston, Australia, December 3–7.
5.
Hammache
,
M.
, and
Gharib
,
M.
,
1991
, “
An Experimental Study of the Parallel and Oblique Vortex Shedding From Circular Cylinders
,”
J. Fluid Mech.
,
232
, pp.
567
590
.10.1017/S0022112091003804
6.
Shih
,
W.
,
Wang
,
C.
,
Coles
,
D.
, and
Roshko
,
A.
,
1993
, “
Experiments on Flow Past Rough Circular Cylinders at Large Reynolds Numbers
,”
J. Wind Eng. Ind. Aerodyn.
,
49
(
1
), pp.
351
368
.10.1016/0167-6105(93)90030-R
7.
Choi
,
J.
,
Jeon
,
W. P.
, and
Choi
,
H.
,
2006
, “
Mechanism of Drag Reduction by Dimples on a Sphere
,”
Phys. Fluids
,
18
, p.
041702
.10.1063/1.2191848
8.
Hwang
,
J. Y.
,
Yang
,
K. S.
, and
Sun
,
S. H.
,
2003
, “
Reduction of Flow-Induced Forces on a Circular Cylinder Using a Detached Splitter Plate
,”
Phys. Fluids
,
15
(
8
), pp.
2433
2436
.10.1063/1.1583733
9.
Shah
,
R. K.
, and
Sekulic
,
D. P.
,
2003
,
Fundamentals of Heat Exchanger Design
,
Wiley
,
New York
.
10.
Khashehchi
,
M.
,
Ashtiani Abdi
,
I.
,
Hooman
,
K.
, and
Roesgen
,
T.
,
2014
, “
A Comparison Between the Wake Behind Finned and Foamed Circular Cylinders in Cross-Flow
,” Experimental Thermal and Fluid Science,
52
, 328–338.
11.
Perrin
,
R.
,
Braza
,
M.
,
Cid
,
E.
,
Cazin
,
S.
,
Barthet
,
A.
,
Sevrain
,
A.
,
Mockett
,
C.
, and
Thiele
,
F.
,
2007
, “
Obtaining Phase Averaged Turbulence Properties in the Near Wake of a Circular Cylinder at High Reynolds Number Using Pod
,”
Exp. Fluids
,
43
(
2–3
), pp.
341
355
.10.1007/s00348-007-0347-6
12.
Shi
,
L. L.
,
Liu
,
Y. Z.
, and
Wan
,
J. J.
,
2010
, “
Influence of Wall Proximity on Characteristics of Wake Behind a Square Cylinder: PIV Measurements and Pod Analysis
,”
Exp. Thermal Fluid Sci.
,
34
(
1
), pp.
28
36
.10.1016/j.expthermflusci.2009.08.008
13.
Godden
,
P. C.
,
2001
, “
Base Pressure Measurements for a Turbine Blade With Span-Wise Trailing Edgecoolant Ejection
,” Ph.D. thesis, University of Queensland, Australia.
14.
Kuppan
,
T.
,
2000
,
Heat Exchanger Design Handbook
,
CRC, Boca Raton
,
FL
.
15.
Adrian
,
R. J.
,
1986
, “
Image Shifting Technique to Resolve Directional Ambiguity in Double-Pulsed Velocimetry
,”
Appl. Opt.
,
25
(
21
), pp.
3855
3858
.10.1364/AO.25.003855
16.
Soria
,
J.
,
Masri
,
A.
, and
Honnery
,
D.
,
1996
, “
An Adaptive Cross-Correlation Digital PIV Technique for Unsteady Flow Investigations
,” Proceedings of the 1st Australian Conference on Laser Diagnostics in Fluid Mechanics and Combustion, Sydney, NSW, Australia, pp. 29–48.
17.
Timmins
,
B. H.
,
2011
,
Automatic Particle Image Velocimetry Uncertainty Quantification
,
Utah State University Press
,
Logan, Utah
.
18.
Ozkan
,
G. M.
,
Oruc
,
V.
,
Akilli
,
H.
, and
Sahin
,
B.
,
2012
, “
Flow Around a Cylinder Surrounded by a Permeable Cylinder in Shallow Water
,”
Exp. Fluids
,
53
(
6
), pp.
1751
1763
.10.1007/s00348-012-1393-2
19.
Sheng
,
J.
,
Meng
,
H.
, and
Fox
,
R. O.
,
2000
, “
A Large Eddy PIV Method for Turbulence Dissipation Rate Estimation
,”
Chem. Eng. Sci.
,
55
(
20
), pp.
4423
4434
.10.1016/S0009-2509(00)00039-7
20.
Richter
,
A.
, and
Naudascher
,
E.
,
1976
, “
Fluctuating Forces on a Rigid Circular Cylinder in Confined Flow
,”
J. Fluid Mech.
,
78
(
3
), pp.
561
576
.10.1017/S0022112076002607
21.
Shaw
,
T. L.
,
1971
, “
Effect of Side Walls on Flow Past Bluff Bodies
,”
J. Hydraul. Div.
,
97
(
1
), pp.
65
79
.
22.
Chen
,
Y.
,
1967
, “
Effect of Confining Walls on the Periodic Wake of 90-Degree Wedges
,” Master's thesis, University of Iowa, Iowa City, IA.
23.
Tozkas
,
A.
,
1965
, “
Effect of Confining Walls on the Periodic Wake of Cylinders and Plates
,” Ph.D. thesis, University of Iowa, Iowa City, IA.
24.
Blackburn
,
H.
, and
Melbourne
,
W.
,
1996
, “
The Effect of Free-Stream Turbulence on Sectional Lift Forces on a Circular Cylinder
,”
J. Fluid Mech.
,
306
, pp.
267
292
.10.1017/S0022112096001309
25.
Moin
,
P.
, and
Mittal
,
R.
,
1997
, “
Suitability of Upwind-Biased Finite Difference Schemes for Large-Eddy Simulation of Turbulent Flows
,”
AIAA J.
,
35
(
8
), pp. 1415–1417.10.2514/2.253
26.
Ong
,
L.
, and
Wallace
,
J.
,
1996
, “
The Velocity Field of the Turbulent Very Near Wake of a Circular Cylinder
,”
Exp. Fluids
,
20
(
6
), pp.
441
453
.10.1007/BF00189383
27.
Balachandar
,
S.
,
Mittal
,
R.
, and
Najjar
,
F.
,
1997
, “
Properties of the Mean Recirculation Region in the Wakes of Two-Dimensional Bluff Bodies
,”
J. Fluid Mech.
,
351
, pp.
167
199
.10.1017/S0022112097007179
28.
Khashehchi
,
M.
,
Ashtiani Abdi
,
I.
,
Hooman
,
K.
, and
Roesgen
,
T.
,
2014
, “
A Comparison Between the Wake Behind Finned and Foamed Circular Cylinders in Cross-Flow
,”
Exp. Thermal Fluid Sci.
,
52
, pp.
328
338
.10.1016/j.expthermflusci.2013.10.008
29.
Breuer
,
M.
,
1998
, “
Large Eddy Simulation of the Subcritical Flow Past a Circular Cylinder: Numerical and Modeling Aspects
,”
Int. J. Numer. Methods Fluids
,
28
(
9
), pp.
1281
1302
.10.1002/(SICI)1097-0363(19981215)28:9<1281::AID-FLD759>3.0.CO;2-#
30.
Feng
,
L.-H.
,
Wang
,
J.-J.
, and
Pan
,
C.
,
2011
, “
Proper Orthogonal Decomposition Analysis of Vortex Dynamics of a Circular Cylinder Under Synthetic Jet Control
,”
Phys. Fluids
,
23
, p.
014106
.10.1063/1.3540679
You do not currently have access to this content.