Turbulent secondary flows are motions in the transverse plane, perpendicular to a main, axial flow. They are encountered in non-circular ducts and can, although the velocity is only of the order of 1–3% of the streamwise bulk velocity, affect the characteristics of the mean flow and the turbulent structure. In this work, the focus is on secondary flow in semi-circular ducts which has previously not been reported. Both numerical and experimental analyses are carried out with high accuracy. It is found that the secondary flow in semi-circular ducts consists of two pairs of counter rotating corner vortices, with a velocity in the range reported previously for related configurations. Agreement between simulation and experimental results are excellent when using a second moment closure turbulence model, and when taking the experimental and numerical uncertainty into account. New and unique results of the secondary flow in semi-circular ducts have been derived from verified simulations and validating laser-based experiments.

References

References
1.
Petterson
,
R. B.
, and
Andersson
,
H.
, 2002,
“Prediction of Turbulence-Generated Secondary Mean Flow in a Square Duct,”
Flow, Turbul. Combust.
,
68
, pp.
41
61
.
2.
Shimizu
,
Y.
,
Futaki
,
Y.
, and
Martin
,
C. S.
, 1992,
“Secondary Flow and Hydraulic Losses within Sinuous Conduits of Rectangular Cross Section,”
J. Fluids Eng.
,
114
, pp.
593
600
.
3.
Liou
,
T.-M.
,
Chen
,
C.-C.
, and
Chen
,
M.-Y.
, 2003,
“Rotating Effect on Fluid Flow in Two Smooth Ducts Connected by a 180-Degree Bend,”
J. Fluids Eng.
,
125
, pp.
138
148
.
4.
Westra
,
R.
,
Broersma
,
L.
,
van Andel
,
K.
, and
Kruyt
,
N.
, 2010,
“PIV Measurements and CFD Computations of Secondary Flow in a Centrifugal Pump Impeller,”
J. Fluids Eng.
,
132
, pp.
0611041
0611048
.
5.
Flack
,
R.
, and
Brun
,
K.
, 2005,
“Fundamental Analysis of the Secondary Flows and Jet-Wake in a Torque Converter Pump - Part II: Flow in a Curved Stationary Passage and Combined Flows,”
J. Fluids Eng.
,
127
, pp.
75
82
.
6.
Demuren
,
A.
, and
Rodi
,
W.
, 1984,
“Calculation of Turbulence-Driven Secondary Motion in Non-Circular Ducts,”
J.Fluid Mech
.,
140
, pp.
189
222
.
7.
Mullinger
,
P.
, and
Jenkins
,
B.
, 2008.
Industrial and Process Furnaces: Principles, Design and Operation,
1st ed.
Butterworth-Heinemann
,
Oxford, UK
.
8.
Bradshaw
,
P.
, 1987,
“Turbulent Secondary Flows,”
Annu. Rev. Fluid Mech.
,
19
, pp.
53
74
.
9.
Rung
,
T.
,
Lübcke
,
H.
,
Thiele
,
F.
,
Fu
,
S.
,
Wang
,
C.
, and
Guo
,
Y.
, 2000,
“Turbulence Closure Model Constraint Derived from Stress-Induced Secondary Flow,”
AIAA J.
,
38
(
9
), pp.
1756
1758
.
10.
Kook Myong
,
H.
, 1991,
“Numerical Investigation of Fully Developed Turbulent Fluid Flow and Heat Transfer in a Square Duct,”
Int. J. Heat Fluid Flow
,
12
(
4
), December, pp.
344
352
.
11.
Rapley
,
C.
, 1982,
“The Simulation of Secondary Flow Effects in Turbulent Non-Circular Passage Flows,”
Int. J. Numer. Methods Fluids
,
2
, pp.
331
347
.
12.
Brundrett
,
E.
, and
Baines
,
W.
, 1964,
“The Production and Diffusion of Vorticity in Duct Flow,”
J. Fluid Mech.
,
19
, pp.
375
394
.
13.
Nakayama
,
A.
,
Chow
,
W.
, and
Sharma
,
D.
, 1983,
“Calculation of Fully Developed Turbulent Flows in Ducts of Arbitrary Cross-Section,”
J. Fluid Mech
.,
128
, pp.
199
217
.
14.
Gessner
,
F.
, and
Jones
,
J.
, 1965,
“On Some Aspects of Fully-Developed Turbulent Flow in Rectangular Channels,”
J. Fluid Mech
.,
23
(
4
), pp.
689
713
.
15.
Melling
,
A.
, and
Whitelaw
,
J.
, 1976,
“Turbulent Flow in a Rectangular Duct,”
J. Fluid Mech
.,
78
(
2
), pp.
289
315
.
16.
Speziale
,
C.
, 1982,
“On Turbulent Secondary Flows in Pipes of Noncircular Cross-Section,”
Int. J. Eng. Sci.
,
20
(
7
), pp.
863
872
.
17.
Fife
,
P.
, 1992,
“Geometrical Aspects of Secondary Motion in Turbulent Duct Flow,”
Theor. Comput. Fluid Dyn.
,
4
, pp.
51
70
.
18.
Haque
,
M.
,
Hassan
,
A.
,
Turner
,
J.
, and
Barrow
,
H.
, 1983,
“An Observation on the Origin of Secondary Flow in Straight Noncircular Ducts,”
Int. J. Heat Mass Transfer
,
17
, pp.
93
95
.
19.
Raiesi
,
H.
,
Piomelli
,
U.
, and
Pollard
,
A.
, 2011,
“Evaluation of Turbulencemodels using Direct Numerical and Large-Eddy Simulation Data,”
J. Fluids Eng.
,
133
, pp.
021203
021212
.
20.
Hurst
,
K.
, and
Rapley
,
C.
, 1991,
“Turbulent Flow Measurements in a 30/60 Degree Right Triangular Duct,”
Int. J. Heat Mass Transfer
,
34
(
3
), pp.
739
748
.
21.
Demuren
,
A.
, 1991,
“Calculation of Turbulence-Driven Secondary Motion in Ducts with Arbitrary Cross Section,”
AIAA J.
,
29
(
4
), pp.
531
537
.
22.
Aly
,
A.
,
Trupp
,
A.
, and
Gerrard
,
A.
, 1978,
“Measurements and Prediction of Fully Developed Turbulent Flow in an Equilateral Triangular Duct,”
J. Fluid Mech
.,
85
(
1
), pp.
57
83
.
23.
Ansys
CFX
, 2009,
Ansys CFX-Solver Theory Guide,
Elsevier Academic Press
. Release 12.1.
24.
Dean
,
R.
, and
Bradshaw
,
P.
, 1976,
“Measurements of Interacting Turbulent Shear Layers in a Duct,”
J. Fluid Mech.
,
78
(
4
), pp.
641
676
.
25.
Hyun
,
B.
,
Balachandar
,
R.
,
Yu
,
K.
, and
Patel
,
V.
, 2003,
“Assessment of PIV to Measure Mean Velocity and Turbulence in Open-Channel Flow,”
Exp. Fluids
,
35
, pp.
262
267
.
26.
Adrian
,
R.
, 1997,
“Dynamic Ranges of Velocity and Spatial Resolution of Particle Image Velocimetry,”
Meas. Sci. Technol.
,
8
, pp.
1393
1398
.
27.
Lavoie
,
P.
,
Avallone
,
G.
,
Gregorio
,
F. D.
,
Romano
,
G.
, and
Antonia
,
R.
, 2007,
“Spatial Resolution of PIV for the Measurement of Turbulence,”
Exp. Fluids
,
43
, pp.
39
51
.
28.
Raffel
,
M.
,
Willert
,
C.
,
Wereley
,
S.
, and
Kompenhans
,
J.
, 2007,
Particle Image Velocimetry: A Practical Guide,
2nd ed.
,
Springer-Verlag
,
Berlin Heidelberg
.
29.
Larsson
,
S.
,
Lindmark
,
E.
,
Lundström
,
S.
,
Marjavaara
,
D.
, and
Töyrä
,
S.
, 2013,
“Visualization of Merging Flow by Usage of PIV and CFD with Application to Grate-Kiln Induration Machines,”
J. App. Fluid Mech.
, Accepted for publication.
30.
Spedding
,
G.
, 2009,
“PIV-Based Investigations of Animal Flight,”
Exp. Fluids
,
46
, pp.
749
763
.
31.
Zhang
,
Z.
, 2004,
“Optical Guidelines and Signal Quality for LDA Applications in Circular Pipes,”
.
Experiments in Fluids
,
37
, pp.
29
39
.
32.
Gardavský
,
J.
Hrbek
,
J.
Chára
,
Z.
and
Severa
,
M.
, 1989,
“Refraction Corrections for LDA Measurements in Circular Tubes within Rectangular Optical Boxes,”
Laser Anemom., Dantec Information
,
8
.
33.
Coleman
,
H.
, and
Steele
,
W.
, 1999,
Experimentation and Uncertainty Analysis for Engineers,
2nd ed
.
John Wiley & Sons
,
New York.
34.
Albrecht
,
H.-E.
,
Borys
,
M.
,
Damaschke
,
N.
, and
Tropea
,
C.
, 2003,
Laser Doppler and Phase Doppler Measurement Techniques
.
Springer Verlag
,
Berlin Heidelberg.
35.
Wilcox
,
D.
, 1986,
“Multiscalemodel for Turbulent Flows,”
In AIAA 24th Aerospace ScienceMeeting
,
American Institute of Aeronautics and Astronautics
.
36.
Menter
,
F.
, 1993,
“Multiscale Model for Turbulent Flows,”
In 24th Fluid Dynamics Conference
,
American Institute of Aeronautics and Astronautics
.
37.
Hellström
,
G.
Marjavaara
,
D.
, and
Lundström
,
S.
, 2007,
“Redesign of a Hydraulic Turbine Draft Tube with Aid of High Performance Computing,”
Adv. Eng. Software
,
38
(
5
), pp.
338
344
.
38.
Coleman
,
H.
, and
Stern
,
F.
, 1997,
“Uncertainties and CFD Code Validation,”
J. Fluids Eng.
,
119
, pp.
795
803
.
39.
Celik
,
I.
,
Ghia
,
U.
,
Roache
,
P
, and
Freitas
,
C.
, 2008,
“Procedure for Estimation and Reporting of Uncertainty Due to Discretization in CFD,”
J. Fluids Eng.
,
130
, pp.
338
344
.
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