Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-06T03:53:48.753Z Has data issue: false hasContentIssue false

Mean drift forces on arrays of bodies due to incident long waves

Published online by Cambridge University Press:  21 April 2006

P. McIver
Affiliation:
Department of Mathematics and Statistics, Brunel University, Uxbridge, Middlesex UB8 3PH, UK

Abstract

The scattering of long water waves by an array of bodies is investigated using the method of matched asymptotic expansions. Two particular geometries are considered: a group of vertical cylinders extending throughout the depth and a group of floating hemispheres. From these solutions, the low-frequency limit of the ratio of the mean drift force on a group of N bodies to that on a single body is calculated. For a wide range of circumstances this drift-force ratio is N2, which is in agreement with previous numerical work. Further drift-force enhancement is possible for certain configurations of vertical cylinders.

Type
Research Article
Copyright
© 1987 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

Abramowitz, M. & Stegun, I. A. 1965 Handbook of Mathematical Functions. Dover.
Balsa, T. F. 1977 Potential flow interactions in an array of cylinders in cross-flow. J. Sound Vib. 50, 285303.Google Scholar
Balsa, T. F. 1982 Low frequency two dimensional flows through a sparse array of bodies J. Sound Vib. 82, 489504.Google Scholar
Balsa, T. F. 1983 Low frequency flows through an array of airfoils. J. Sound Vib. 86, 353367.Google Scholar
Eatock-Taylor, R. & Hung, S. M. 1985 Wave drift enhancement effects in multi-column structures. Appl. Ocean Res. 7, 128137.Google Scholar
Eatock-Taylor, R. & Hung, S. M. 1986 Wave drift enhancement effects for semi-submersible and TLP systems. Proc. 5th Offshore Mechanics and Arctic Engineering Symp., Tokyo, vol. 1. pp. 273280. ASME.
Hulme, A. 1982 The wave forces acting on a floating hemisphere undergoing forced periodic oscillations. J. Fluid Mech. 121, 443463.Google Scholar
Kagemoto, H. & Yue, D. K. P. 1986 Interactions among multiple three-dimensional bodies in water waves: an exact algebraic method. J. Fluid Mech. 166, 189209.Google Scholar
Maruo, H. 1960 The drift of a body floating in waves. J. Ship Res. 4, 110.Google Scholar
Mei, C. C. 1983 The Applied Dynamics of Ocean Surface Waves. Wiley-Interscience.
Miles, J. W. & Gilbert, J. F. 1968 Scattering of gravity waves by a circular dock. J. Fluid Mech. 34, 783793.Google Scholar
Newman, J. N. 1967 The drift force and moment on ships in waves. J. Ship Res. 11, 5160.Google Scholar
Newman, J. N. 1974 Second-order, slowly varying forces on vessels in irregular waves. Proc. Intl Symp. on the Dynamics of Marine Vehicles and Structures in Waves, University College, London, pp. 182186.
Pinkster, J. A. 1979 Mean and low frequency drifting forces on floating structures. Ocean Engng 6, 593615.Google Scholar
Thorne, R. C. 1953 Multipole expansions in the theory of surface waves. Proc. Camb. Phil. Soc. 49, 707716.Google Scholar
Van Dyke, M. 1975 Perturbation Methods in Fluid Mechanics. Stanford: Parabolic Press.