Simulations are carried out for linear shear flow past a rotating elliptic cylinder to investigate the effect of shear flow on hovering vortex. An in-house fluid solver that is based on immersed boundary method (IBM) is used to study the flow features and variation in aerodynamic forces. The simulations are carried out for various nondimensional rotation rates, axis ratio (AR) of the cylinder, and shear parameter. In shear flow past rotating elliptic cylinder, the negative vortices are sustained for longer distances in the downstream of the cylinder, and due to the velocity gradient, the sequence of the vortex street changes. It also has significant effect on the formation and composition of hovering vortex. To capture these features, each vortex is tracked as they form, detach, and move in the wake of the cylinder. Hovering vortex, formed due to coalescing of multiple vortices near the cylinder, is subdued for smaller rotation rates at moderate shear. It is also observed that lift forces increase linearly with shear, while the frequency of shedding shows no dependency on shear parameter.

References

1.
Jordan
,
S. K.
, and
Fromm
,
J. E.
,
1972
, “
Laminar Flow past a Circle in a Shear Flow
,”
Phys. Fluids
,
15
(
6
), pp.
972
976
.
2.
Kiya
,
M.
,
Tamura
,
H.
, and
Arie
,
M.
,
1980
, “
Vortex Shedding From a Circular Cylinder in Moderate Reynolds Number Flow
,”
J. Fluid Mech.
,
101
(
4
), pp.
721
735
.
3.
Kwon
,
T. S.
,
Sung
,
H. J.
, and
Hyun
,
J. M.
,
1992
, “
Experimental Investigation of Uniform-Shear Flow Past a Circular Cylinder
,”
ASME J. Fluids Eng.
,
114
(
3
), pp.
457
460
.
4.
Lei
,
C.
,
Cheng
,
L.
, and
Kavanagh
,
K.
,
2000
, “
A Finite Difference Solution of the Shear Flow Over a Circular Cylinder
,”
Ocean Eng.
,
27
(
3
), pp.
271
290
.
5.
Kang
,
S.
,
2006
, “
Uniform-Shear Flow Over a Circular Cylinder at Low Reynolds Numbers
,”
J. Fluids Struct.
,
22
(
4
), pp.
541
555
.
6.
Cao
,
S.
,
Ozono
,
S.
,
Tamura
,
Y.
,
Ge
,
Y.
, and
Kikugawa
,
H.
,
2010
, “
Numerical Simulation of Reynolds Number Effects on Velocity Shear Flow Around a Circular Cylinder
,”
J. Fluids Struct.
,
26
(
5
), pp.
685
702
.
7.
Thompson
,
M. C.
,
Radi
,
A.
,
Rao
,
A.
,
Sheridan
,
J.
, and
Hourigan
,
K.
,
2014
, “
Low-Eynolds-Number Wakes of Elliptical Cylinders: From the Circular Cylinder to the Normal Flat Plate
,”
J. Fluid Mech.
,
751
, pp.
570
600
.
8.
Leontini
,
J. S.
,
Jacono
,
D. L.
, and
Thompson
,
M. C.
,
2015
, “
Stability Analysis of the Elliptic Cylinder Wake
,”
J. Fluid Mech.
,
763
, pp.
302
321
.
9.
Griffith
,
M. D.
,
Jacono
,
D. L.
,
Sheridan
,
J.
, and
Leontini
,
J. S.
,
2016
, “
Passive Heaving of Elliptical Cylinders With Active Pitching From Cylinders Towards Flapping Foils
,”
J. Fluids Struct.
,
67
, pp.
124
141
.
10.
Sung
,
H. J.
,
Chun
,
C. K.
, and
Hyun
,
J. M.
,
1995
, “
Experimental Study of Uniform-Shear Flow past a Rotating Cylinder
,”
ASME J. Fluids Eng.
,
117
(
1
), pp.
62
67
.
11.
Chew
,
Y. T.
,
Luo
,
S. C.
, and
Cheng
,
M.
,
1997
, “
Numerical Study of a Linear Shear Flow past a Rotating Cylinder
,”
J. Wind Eng. Ind. Aerodyn.
,
66
(
2
), pp.
107
125
.
12.
Kang
,
S.
,
2006
, “
Laminar Flow Over a Steadily Rotating Circular Cylinder Under the Influence of Uniform Shear
,”
Phys. Fluids
,
18
(
4
), p.
0471060
.http://www.homepages.ed.ac.uk/shs/Climatechange/Flettner%20ship/Kang.pdf
13.
Fallah
,
K.
,
Fardad
,
A.
,
Fattahi
,
E.
,
Zadeh
,
N. S.
, and
Ghaderi
,
A.
,
2012
, “
Numerical Simulation of Planar Shear Flow Passing a Rotating Cylinder at Low Reynolds Numbers
,”
Acta Mech.
,
223
(
2
), pp.
221
236
.
14.
Rao
,
A.
,
Leontini
,
J.
,
Thompson
,
M. C.
, and
Hourigan
,
K.
,
2013
, “
Three-Dimensionality in the Wake of a Rotating Cylinder in a Uniform Flow
,”
J. Fluid Mech.
,
717
, pp.
1
29
.
15.
Rao
,
A.
,
Radi
,
A.
,
Leontini
,
J. S.
,
Thompson
,
M. C.
,
Sheridan
,
J.
, and
Hourigan
,
K.
,
2015
, “
A Review of Rotating Cylinder Wake Transitions
,”
J. Fluids Struct.
,
53
, pp.
2
14
.
16.
Alawadhi
,
E. M.
,
2015
, “
Flow past an Elliptical Cylinder Undergoing Rotationally Oscillating Motion
,”
ASME J. Fluids Eng.
,
137
(
3
), p.
031106
.
17.
Naik
,
S. N.
,
Vengadesan
,
S.
, and
Prakash
,
K. A.
,
2017
, “
Numerical Study of Fluid Flow past a Rotating Elliptic Cylinder
,”
J. Fluids Struct.
,
68
, pp.
15
31
.
18.
Lua
,
K. B.
,
Lim
,
T. T.
, and
Yeo
,
K. S.
,
2010
, “
A Rotating Elliptic Airfoil in Fluid at Rest and in a Parallel Free Stream
,”
Exp. Fluids
,
49
(
5
), pp.
1065
1084
.
19.
Peskin
,
C. S.
,
1982
, “
The Fluid Dynamics of Heart Valves: Experimental, Theoretical and Computational Methods
,”
Annu. Rev. Fluid Mech.
,
14
(
1
), pp.
235
259
.
20.
Mittal
,
R.
, and
Iaccarino
,
G.
,
2005
, “
Immersed Boundary Method
,”
Annu. Rev. Fluid Mech.
,
37
(
1
), pp.
239
261
.
21.
Su
,
S.-W.
,
Lai
,
M.-C.
, and
Lin
,
C.-A.
,
2007
, “
An Immersed Boundary Technique for Simulating Complex Flows With Rigid Boundary
,”
Comput. Fluids
,
36
(
2
), pp.
313
324
.
22.
Sudhakar
,
Y.
, and
Vengadesan
,
S.
,
2009
, “
Flight Force Production by Flapping Insect Wings in Inclined Stroke Plane Kinematics
,”
Comput. Fluids
,
39
(
4
), pp.
683
695
.
23.
Raman
,
S. K.
,
Prakash
,
K. A.
, and
Vengadesan
,
S.
,
2013
, “
Effect of Axis Ratio on Fluid Flow Around an Elliptic Cylinder: A Numerical Study
,”
ASME J. Fluids Eng.
,
135
(
11
), p. 111201.
24.
Shaafi
,
K.
, and
Vengadesan
,
S.
,
2014
, “
Wall Proximity Effects on the Effectiveness of Upstream Control Rod
,”
J. Fluids Struct.
,
49
, pp.
112
134
.
25.
Shaafi
,
K.
,
Naik
,
S. N.
, and
Vengadesan
,
S.
,
2017
, “
Effect of Rotating Cylinder on Wake-Wall Interactions
,”
Ocean Eng.
,
139
, pp.
275
286
.
26.
Paul
,
I.
,
Prakash
,
K. A.
,
Vengadesan
,
S.
, and
Pulletikurthi
,
V.
,
2016
, “
Analysis and Characterization of Momentum and Thermal Wakes of Elliptic Cylinders
,”
J. Fluid Mech.
,
807
, pp.
303
323
.
27.
Jeong
,
J.
, and
Hussain
,
F.
,
1995
, “
On the Identification of a Vortex
,”
J. Fluid Mech.
,
285
(
1
), pp.
69
94
.
28.
Sadarjoen
,
I. A.
, and
Post
,
F. H.
,
2000
, “
Detection, Quantification, and Tracking of Vortices Using Streamline Geometry
,”
Comput. Graph.
,
24
(
3
), pp.
333
341
.
29.
Cao
,
S.
,
Ozono
,
S.
,
Hirano
,
K.
, and
Tamura
,
Y.
,
2007
, “
Vortex Shedding and Aerodynamic Forces on a Circular Cylinder in Linear Shear Flow at Subcritical Reynolds Number
,”
J. Fluids Struct.
,
23
(
5
), pp.
703
714
.
30.
Sumner
,
D.
, and
Akosile
,
O.
,
2003
, “
On Uniform Planar Shear Flow Around a Circular Cylinder at Subcritical Reynolds Number
,”
J. Fluids Struct.
,
18
(
3–4
), pp.
441
454
.
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