Flows past a free surface piercing cylinder are studied numerically by large eddy simulation at Froude numbers up to $FrD=3.0$ and Reynolds numbers up to $ReD=1×105$. A two-phase volume of fluid technique is employed to simulate the air-water flow and a flux corrected transport algorithm for transport of the interface. The effect of the free surface on the vortex structure in the near wake is investigated in detail together with the loadings on the cylinder at various Reynolds and Froude numbers. The computational results show that the free surface inhibits the vortex generation in the near wake, and as a result, reduces the vorticity and vortex shedding. At higher Froude numbers, this effect is stronger and vortex structures exhibit a 3D feature. However, the free surface effect is attenuated as Reynolds number increases. The time-averaged drag force on the unit height of a cylinder is shown to vary along the cylinder and the variation depends largely on Froude number. For flows at $ReD=2.7×104$, a negative pressure zone is developed in both the air and water regions near the free surface leading to a significant increase of drag force on the cylinder in the vicinity of the free surface at about $FrD=2.0$. The mean value of the overall drag force on the cylinder increases with Reynolds number and decreases with Froude number but the reduction is very small for $FrD=1.6–2.0$. The dominant Strouhal number of the lift oscillation decreases with Reynolds number but increases with Froude number.

1.
Wickramasinghe
,
D.
, and
Wilkinson
,
R. H.
, 1997, “
Wakes and Waves Generated by Surface Piercing Cylinders
,” DRA Study Report No. EX 3545.
2.
Inoue
,
M.
,
Baba
,
N.
, and
Himeno
,
Y.
, 1993, “
Experimental and Numerical Study of Viscous Flow Field Around an Advancing Vertical Circular Cylinder Piercing a Free Surface
,”
J. Kansai Soc. Nav. Archit.
1346-7727,
220
, pp.
57
64
.
3.
Ferrant
,
P.
, and
Guillern
,
P. E.
, 1998, “
Interaction of Second Order Wave Packets With a Vertical Cylinder
,”
Proceedings of the 8th International Offshore Polar Engineering Conference
,
, May 24–29, Vol.
III
, pp.
340
347
.
4.
Tseng
,
M. H.
,
Yen
,
C. L.
, and
Song
,
C. C. S.
, 2000, “
Computation of Three-Dimensional Flow Around Square and Circular Piers
,”
Int. J. Numer. Methods Fluids
0271-2091,
34
, pp.
207
227
.
5.
Kawamura
,
T.
,
Mayer
,
S.
,
Garapon
,
A.
, and
Sorensen
,
L.
, 2002, “
Large Eddy Simulation of a Flow Past a Free Surface Piercing Circular Cylinder
,”
ASME J. Fluids Eng.
0098-2202,
124
, pp.
91
101
.
6.
Brackbill
,
J. U.
,
Kothe
,
D. B.
, and
Zemach
,
C.
, 1992, “
A Continuum Method for Modeling Surface Tension
,”
J. Comput. Phys.
0021-9991,
100
, pp.
335
354
.
7.
Smagorinsky
,
J.
, 1963, “
General Circulation Experiments With the Primitive Equations I. The Basic Experiment
,”
Mon. Weather Rev.
0027-0644,
91
, pp.
99
164
.
8.
Van Driest
,
E. R.
, 1956, “
On Turbulent Flow Near a Wall
,”
J. Aeronaut. Sci.
0095-9812,
23
, pp.
1007
1011
.
9.
Piomelli
,
U.
,
Moin
,
P.
, and
Ferziger
,
J. H.
, 1988, “
Model Consistency in Large Eddy Simulation of Turbulent Channel Flows
,”
Phys. Fluids
0031-9171,
31
, pp.
1884
1891
.
10.
Szepessy
,
S.
, and
Bearman
,
P. W.
, 1992, “
Aspect Ratio and End Effects on Vortex Shedding From a Circular Cylinder
,”
J. Fluid Mech.
0022-1120,
234
,
191
217
.
11.
Breuer
,
M.
, 1998, “
Large Eddy Simulation of the Subcritical Flow Past a Circular Cylinder: Numerical and Modeling Aspects
,”
Int. J. Numer. Methods Fluids
0271-2091,
28
, pp.
1281
1302
.
12.
Rudman
,
M.
, 1997, “
Volume-Tracking Methods for Interfacial Flow Calculations
,”
Int. J. Numer. Methods Fluids
0271-2091,
24
, pp.
671
691
.
13.
Orlanski
,
I.
, 1976, “
Simple Boundary Condition for Unbounded Hyperbolic Flows
,”
J. Comput. Phys.
0021-9991,
21
, pp.
251
269
.
14.
Heinrich
,
J. C.
,
Idelsohn
,
S. R.
,
Oñate
,
E.
, and
Vionnet
,
C. A.
, 1996, “
Boundary Conditions for Finite Element Simulations of Convective Flows With Artificial Boundaries
,”
Int. J. Numer. Methods Fluids
0271-2091,
39
, pp.
1053
1071
.
15.
Peskin
,
C. S.
, 1977, “
Numerical Simulations of Blood Flow in the Heart
,”
J. Comput. Phys.
0021-9991,
25
, pp.
220
252
.
16.
Youngs
,
D. L.
, 1984, “
An Interface Tracking Method for a 3D Eulerian Hydrodynamics Code
,” AWRE, Technical Report No. 44/92/35.
17.
Gerrard
,
J. H.
, 1966, “
The Mechanics of the Formation Region of Vortices Behind Bluff Bodies
,”
J. Fluid Mech.
0022-1120,
25
, pp.
401
413
.
18.
Mittal
,
R.
, and
Balachandar
,
S.
, 1995, “
Effect of Three-Dimensionality on the Lift and Drag of Nominally Two-Dimensional Cylinders
,”
Phys. Fluids
1070-6631,
7
(
8
), pp.
1841
1865
.
19.
Jeong
,
J.
, and
Hussain
,
F.
, 1995, “
On the Identification of a Vortex
,”
J. Fluid Mech.
0022-1120,
285
, pp.
69
94
.
20.
Roshko
,
A.
, 1961, “
Experiments on the Flow Past a Circular Cylinder at Very High Reynolds Numbers
,”
J. Fluid Mech.
0022-1120,
10
, pp.
345
356
.
21.
Wieselsberger
,
C.
, 1921, “
Neuere Festellungen über die Gesetze des Flüssigkeits-und Luftwiderstands
,”
Phys. Z.
0369-982X,
22
, pp.
321
328
.