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Waves caused by a moving disturbance in a shallow channel of finite width

Published online by Cambridge University Press:  21 April 2006

R. C. Ertekin
Affiliation:
Department of Naval Architecture & Offshore Engineering, University of California, Berkeley Present address: Department of Ocean Engineering, University of Hawaii, Honolulu.
W. C. Webster
Affiliation:
Department of Naval Architecture & Offshore Engineering, University of California, Berkeley
J. V. Wehausen
Affiliation:
Department of Naval Architecture & Offshore Engineering, University of California, Berkeley

Abstract

The flow created by an impulsively started pressure distribution travelling at a constant velocity in a shallow channel is investigated. The restricted Green-Naghdi theory of fluid sheets is used to perform the three-dimensional calculations. The results show remarkable similarity to model tests. In particular, these calculations predict the periodic generation of two-dimensional solitons in front of and travelling faster than the disturbance if the disturbance is large enough. Behind the disturbance a complicated, doubly corrugated set of waves is formed. The computations also predict that periodic creation of solitons is accompanied by a correspondingly periodic oscillation of the wave drag, as well as a dramatic increase in the mean wave drag.

Type
Research Article
Copyright
© 1986 Cambridge University Press

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References

Akylas, T. R. 1984 On the excitation of long nonlinear water waves by a moving pressure distribution. J. Fluid Mech. 141, 455466.Google Scholar
Ames, W. F., Lee, S. Y. & Zaiser, J. N. 1968 Nonlinear vibration of a traveling threadline. Intl J. Non-linear Mech. 3, 449469.Google Scholar
Cole, S. L. 1985 Transient waves produced by flow past a bump. Wave Motion 7, 579587.Google Scholar
Ertekin, R. C. 1984 Soliton generation by moving disturbances in shallow water: theory, computation and experiment. Ph.D. dissertation, University of California, Berkeley.
Ertekin, R. C., Webster, W. C. & Wehausen, J. V. 1984 Ship-generated solitons. Proc. 15th Symp. Naval Hydrodynam., Hamburg, pp. 347–364.
Graff, W. 1962 Untersuchungen über die Ausbildung des Wellenwiderstandes im Bereich der Stauwellengeschwindigkeit in flachem, seitlich beschränktem Fahrwasser. Schiffstechnik 9, 110122.Google Scholar
Green, A. E., Laws, N. & Naghdi, P. M. 1974 On the theory of water waves. Proc. R. Soc. Lond. A338, 4355.Google Scholar
Green, A. E., & Naghdi, P. M. 1976a Directed fluid sheets. Proc. R. Soc. Lond. A347, 447473.Google Scholar
Green, A. E. & Naghdi, P. M. 1976b A derivation of equations for wave propagation in water of variable depth. J. Fluid Mech. 78, 237246.Google Scholar
Green, A. E. & Naghdi, P. M. 1977 Water waves in a nonhomogeneous incompressible fluid. Trans. ASME E: J. Appl. Mech. 44, 523528.Google Scholar
Huang, De-Bo, Sibul, O. J. & Wehausen, J. V. 1982a Ships in very shallow water. Festkolloquium zur Emeritierung von Karl Wieghardt, März 1982, Institut für Schiffbau der Universität Hamburg, Bericht Nr. 427 (April 1983), pp. 2949.
Huang, De-Bo, Sibul, O. J., Webster, W. C., Wehausen, J. V., Wu, De-Ming & Wu, T. Y. 1982b, Ships moving in the transcritical range. Conf. on Behaviour of Ships in Restricted Waters, Varna. Proc. vol. 2, pp. 26/1-26/10.
Longuet-Higgins, M. S. & Cokelet, E. D. 1976 The deformation of steep surface waves on water. I. A numerical method of computation. Proc. R. Soc. Lond. A350, 126.Google Scholar
Mei, C. C. 1986 Radiation of solitons slender bodies advancing in a shallow channel. J. Fluid Mech. 162, 5367.Google Scholar
Rayleigh, Lord 1876 On waves. Phil. Mag. (5) 1, 257279. (Scientific pdapers 1, 251–271.)Google Scholar
Shapiro, R. 1975 Linear filtering. Maths Comput. 29, 10941097.Google Scholar
Sturtzel, W. & Graff, W. 1958 Untersuchungen der in stehendem und strömendem Wasser festgestellten Änderungen des Schiffswiderstandes durch Druckmessungen. Forschungsberichte des Wirtschafts- und Verkehrsministeriums Nordrhein-Westfalen, Nr. 618, 34 pp.Google Scholar
Thews, J. G. & Landweber, L. 1935 The influence of shallow water on the resistance of a cruiser model. U.S. Experimental Model Basin, Navy Yard, Washington, D.C., Rep. No. 408, 31 pp.
Wu, T. Y. 1981 Long waves in ocean and coastal waters. J. Engng Mech. Div. ASCE 107, 501522.Google Scholar
Wu, De-Ming & Wu, T. Y. 1982 Three-dimensional nonlinear long waves due to moving surface pressure. Proc. 14th Symp. Naval Hydrodynam., Ann Arbor, Mich., pp. 103129.
Yeung, R. W. 1982 Numerical methods in free-surface flows. Ann. Rev. Fluid Mech. 14, 395442.Google Scholar