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The extended Korteweg-de Vries equation and the resonant flow of a fluid over topography

Published online by Cambridge University Press:  26 April 2006

T. R. Marchant
Affiliation:
Department of Mathematics, The University of Wollongong, PO Box 1144. Wollongong, NSW 2500, Australia
N. F. Smyth
Affiliation:
Department of Mathematics, The University of Wollongong, PO Box 1144. Wollongong, NSW 2500, Australia

Abstract

The extended Korteweg-de Vries equation which includes nonlinear and dispersive terms cubic in the wave amplitude is derived from the water-wave equations and the Lagrangian for the water-wave equations. For the special case in which only the higher-order nonlinear term is retained, the extended Korteweg-de Vries equation is transformed into the Korteweg-de Vries equation. Modulation equations for this equation are then derived from the modulation equations for the Korteweg-de Vries equation and the undular bore solution of the extended Korteweg-de Vries equation is found as a simple wave solution of these modulation equations. The modulation equations are also used to extend the solution for the resonant flow of a fluid over topography. This resonant flow occurs when, in the weakly nonlinear, long-wave limit, the basic flow speed is close to a linear long-wave phase speed for one of the long-wave modes. In addition to the effect of higher-order terms, the effect of boundary-layer viscosity is also considered. These solutions (with and without viscosity) are compared with recent experimental and numerical results.

Type
Research Article
Copyright
© 1990 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
Baines, P. G.: 1984 A unified description of two-layer flow over topography. J. Fluid Mech. 146, 127167.Google Scholar
Byatt-Smith, J. G. B.: 1987 Perturbation theory for approximately integrable partial differential equations and the change of amplitude of solitary-wave solutions of the BBM equation. J. Fluid Mech. 182, 467483.Google Scholar
Chow, K. W.: 1989 A second order solution for the solitary wave in a rotational flow. Phys. Fluids A 1 (7), 12351239.Google Scholar
Cole, S. L.: 1985 Transient waves produced by flow past a bump. Wave Motion 7, 579587.Google Scholar
Flaschka, H., Forest, M. G. & Mclaughlin, D. W., 1980 Multiphase averaging and the inverse spectral solution of the Korteweg-de Vries equation. Commun. Pure Appl. Maths 33, 739784.Google Scholar
Fornberg, B. & Whitham, G. B., 1978 A numerical and theoretical study of certain nonlinear wave phenomena. Phil. Trans. R. Soc. Lond. A 289, 373404.Google Scholar
Gear, J. & Grimshaw, R., 1983 A second order theory for solitary waves in shallow fluids. Phys. Fluids 26, 1429.Google Scholar
Grimshaw, R. H. J.: 1983 Solitary waves in density stratified fluids. In Nonlinear Deformation Waves, IUTAM Symp., Tallinn, 1982 (ed. U. Nigel & J. Engelbrecht), pp. 431447. Springer.
Grimshaw, R. H. J. & Smyth, N. F. 1986 Resonant flow of a stratified fluid over topography. J. Fluid Mech. 169, 429464.Google Scholar
Gurevich, A. V. & Pitaevskii, L. P., 1974 Nonstationary structure of a collisionless shock wave. Sov. Phys., J. Exp. Theor. Phys. 38, 291297.Google Scholar
Helfrich, K. R., Melville, W. K. & Miles, J. W., 1984 On interfacial solitary waves over slowly varying topography. J. Fluid Mech. 149, 305317.Google Scholar
Huang, D.-B., Sibel, G. J., Webster, W. C., Wehausen, J. V., Wu, D.-M. & Wu, T. Y. 1982 Ships moving in the transcritical range. In Proc. Conf. on Behaviour of Ships in Restricted Waters, Varna, vol. 2, pp. 26-126-10.
Kakutani, T. & Yamasaki, N., 1978 Solitary waves on a two-layer fluid. J. Phys. Soc. Japan 45, 674679.Google Scholar
Kaup, D. J. & Newell, A. C., 1978 Solitons as particles, oscillators and in slowly changing media: a singular perturbation theory. Proc. R. Soc. Lond. A 361, 413446.Google Scholar
Laitone, E. V.: 1960 The second approximation to cnoidal and solitary waves. J. Fluid Mech. 9, 430444.Google Scholar
Lee, S.-J.: 1985 Generation of long water waves by moving disturbances. PhD thesis, California Institute of Technology.
Lee, S.-J., Yates, G. T. & Wu, T. Y., 1989 Experiments and analysis of upstream advancing solitary waves generated by moving disturbances. J. Fluid Mech. 199, 569593.Google Scholar
Leone, C., Segur, H. & Hammack, J. L., 1982 Viscous decay of long internal solitary waves. Phys. Fluids 25, 942944.Google Scholar
Long, R. R.: 1956 Solitary waves in one- and two-fluid systems. Tellus 8, pp. 460471.Google Scholar
Luke, J. C.: 1967 A variational principle for a fluid with a free surface. J. Fluid Mech. 27, 395397.Google Scholar
Melville, W. K. & Helfrich, K. R., 1987 Transcritical two-layer flow over topography. J. Fluid Mech. 178, 3152.Google Scholar
Miles, J. W.: 1979 On internal solitary waves. Tellus 31, 456462.Google Scholar
Smyth, N. F.: 1987 Modulation theory solution for resonant flow over topography. Proc. R. Soc. Lond. A 409, 7997.Google Scholar
Smyth, N. F.: 1988 Dissipative effects on the resonant flow of a stratified fluid over topography. J. Fluid Mech. 192, 287312.Google Scholar
Whitham, G. B.: 1965a A general approach to linear and nonlinear dispersive waves using a Lagrangian. J. Fluid Mech. 22, 273283.Google Scholar
Whitham, G. B.: 1965b Non-linear dispersive waves. Proc. R. Soc. Lond. A 283, 238261.Google Scholar
Whitham, G. B.: 1967 Variational methods and applications to water waves. Proc. R. Soc. Lond. A 299, 625.Google Scholar
Whitham, G. B.: 1974 Linear and Nonlinear Waves. Wiley-Interscience.
Wu, D. M. & Wu, T. Y., 1982 Three-dimensional nonlinear long waves due to moving surface pressure. In Proc. 14th Symp. on Naval Hydrodynamics, Ann Arbor.
Wu, T. Y.: 1987 Generation of upstream advancing solitons by moving disturbances. J. Fluid Mech. 184, 7599.Google Scholar