Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-18T21:38:38.807Z Has data issue: false hasContentIssue false
  • English
  • Français

Force on a circular cylinder in viscous oscillatory flow at low Keulegan—Carpenter numbers

Published online by Cambridge University Press:  21 April 2006

Turgut Sarpkaya
Turgut Sarpkaya
Affiliation:
Mechanical Engineering, Naval Postgraduate School, Monterey, California 93943, USA
Get access Rights & Permissions [Opens in a new window]

Abstract

This paper presents the in-line force coefficients for circular cylinders in planar oscillatory flows of small amplitude. The results are compared with the theoretical predictions of Stokes (1851) and Wang (1968). For two-dimensional, attached- and laminar-flow conditions the data are, as expected, in good agreement with the Stokes–Wang analysis. The oscillatory viscous flow becomes unstable to axially periodic vortices above a critical Keulegan–Carpenter number K (K = UmT/D, Um = the maximum velocity in a cycle, T = the period of flow oscillation, and D = the diameter of the circular cylinder) for a given β (β = Re/K = D2/vT, Re = UmD/v, and v = the kinematic viscosity of fluid) as shown experimentally by Honji (1981) and theoretically by Hall (1984). The present investigation has shown that the Keulegan—Carpenter number at which the drag coefficient Cd deviates rather abruptly from the Stokes—Wang prediction nearly corresponds to the critical K at which the vortical instability occurs.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 165 , April 1986 , pp. 61 - 71
Copyright
© 1986 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bearman, P. W. 1985 Vortex trajectories in oscillating flow. In Proc. of Separated Flow Around Marine Structures, Trondheim, Norway, pp. 133–153 The Norwegian Institute of Technology, Trondheim, Norway.
Bearman, P. W., Downie, M. J., Graham, J. M. R. & Obasaju, E. D. 1985 Forces on cylinders in viscous oscillatory flow at low Keulegan—Carpenter numbers. J. Fluid Mech. 154, 337–356.Google Scholar
Bearmanv, P. W., Graham, J. M. R., Naylor, P. & Obasaju, E. D. 1981 The role of vortices in oscillatory flow about bluff cylinders. In Proc. Intl Symp. on Hydrodynamics in Ocean Engng, Trondheim, Norway, August, pp. 621–635.
Hall, P. 1984 On the stability of unsteady boundary layer on a cylinder oscillating transversely in a viscous fluid. J. Fluid Mech. 146, 347–367.Google Scholar
Honji, H. 1981 Streaked flow around an oscillating circular cylinder. J. Fluid Mech. 107, 509–520.Google Scholar
Keulegan, G. H. & Carpenter, L. H. 1958 Forces on cylinders and plates in an oscillating fluid. J. Res. Nat. Bur. Standards 60, 423–440.Google Scholar
Morison, J. R., O'Brien, M. P., Johnson, J. W. & Schaaf, S. A. 1950 The force exerted by surface waves on piles. Petroleum Trans. 189, 149–157.Google Scholar
Rosenhead, L. (ed.) 1963 Laminar Boundary Layers. Clarendon.
Sarpkaya, T. 1976 Vortex shedding and resistance in harmonic flow about smooth and rough circular cylinders at high Reynolds numbers. Tech. Rep. No. NPS-59SL76021, Naval Postgraduate School, Monterey, CA.Google Scholar
Sarpkaya, T. 1977 In-line and transverse forces on cylinders in oscillatory flow at High Reynolds numbers. J. Ship Res. 21, 200–216.Google Scholar
Sarpkaya, T. 1985 Past progress and outstanding problems in time-dependent flows about ocean structures. In Proc. of Separated Flow Around Marine Structures, Trondheim, Norway, pp. 1–36. The Norwegian Institute of Technology, Trondheim, Norway.
Sarpkaya, T. & Isaacson, M. 1981 Mechanics of Wave Forces on Offshore Structures. New York: Van Nostrand Reinhold.
Stokes, G. G. 1851 On the effect of the internal friction of fluids on the motion of pendulums. Trans. Camb. Phil. Soc. 9, 8–106.Google Scholar
Wang, C.-Y. 1968 On high-frequency oscillating viscous flows. J. Fluid Mech. 32, 55–68.Google Scholar
Williamson, C. H. K. 1985 Sinusoidal flow relative to circular cylinders. J. Fluid Mech. 155, 141–174.Google Scholar