Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-08T05:37:51.680Z Has data issue: false hasContentIssue false

The bifurcation of steady gravity water waves in (R, S) parameter space

Published online by Cambridge University Press:  26 April 2006

S. H. Doole
Affiliation:
Department of Engineering Mathematies, Bristol University, Queen's Building, University Walk, Bristol BS8 ITR, UK
J. Norbury
Affiliation:
Mathematical Institute, Oxford University, 24-29 St. Giles’, Oxford OXI 3LB, UK

Abstract

The bifurcation of steady periodic waves from irrotational inviscid streamflows is considered. Normalizing the flux Q to unity leaves two other natural quantities R (pressure head) and S (flowforce) to parameterize the wavetrain. In a well-known paper, Benjamin & Lighthill (1954) presented calculations within a cnoidal-wave theory which suggested that the corresponding values of R and S lie inside the cusped locus traced by the sub- and supercritical streamflows. This rule has been applied since to many other flow scenarios. In this paper, regular expansions for the streamfunction and profile are constructed for a wave forming on a subcritical stream and thence values for R and S are calculated. These describe, locally, how wave brances in (R, S) parameter space point inside the streamflow cusp. Accurate numerics using a boundry-integral solver show how these constant-period branches extend globally and map out parameter space. The main result is to show that the large-amplitude branches for all steady Stokes’ waves lie surprisingly close to the subcritical stream branch, This has important consequences for the feasibility of undular bores (as opposed to hydraulic jumps) in obstructed flow. Moreover, the transition from the ‘long-wave region’ towards the ‘deep-water limit’ is char-acterized by an extreme geometry, bith of the wave branches and how they sit inside each other. It is also shown that a single (Q, R, S) trriple may represent more than one wave since the global branches can overlap in (R, S) parameter space. This non-uniqueness is not that associated with the known premature maxima of wave propertties as functions of wave amplitude near waves of greatest height.

Type
Research Article
Copyright
© 1995 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

Aston, P. J. 1991 Analysis and computation of symmetry-breaking bifurcation and scaling laws using group theoretic methods. SIAM J. Math. Anal. 22, 181212.Google Scholar
Baesens, C. & Mackay, R. S. 1992 Uniformly travelling waves from a dynamical systems viewpoint: ome insights into bifurcations from Stokes’ family. J. fluid Mech. 241, 333347.Google Scholar
Benjamin, T. B. 1956 On the flew in channels when rigid obstacles are placed in the stream.. J. Fluid Mech. 1, 22748.Google Scholar
Benjamin, T. B. 1984 Impulse, flow force and variational principles. IMA J. Appl. Maths 32, 368.Google Scholar
Benjamin, T. B. 1995 Verification of the Benjamin-Lighthill conjecture about steady water waves. J. Fluid Mech. 295, 337356.Google Scholar
Benjamin, T. B. & Lighthill, M. J. 1954 On cnoidal waves and bores.. Proc. R. Soc. Lond. A 224, 448460 (referred to Herein as BL).Google Scholar
Benjamin, T. B. & Olver, P. J. 1982 Hamiltonian structure, symmetries and conservation laws for water waves.. J. Fluid Mech. 125, 137185.Google Scholar
Bland, D. R. 1988 Wave Theory and Applications. Oxford University Press.
Bridges, T. J. 1992 Spatial Hamiltonian structure, energy flux and the water-wave problem.. Proc. R. Soc. Lond. A 439 297315.Google Scholar
Budden, P. & Norbury, J. 1977 Sluice gate problems with gravity. Math. Proc, Camb, Phill. Soc. 81, 157175.Google Scholar
Chandler, G. A. & Graham, I. G. 1993 The computation of water waves modelled by Nekrasov's equation. SIAM J. Numer. Anal. 30, 10411065.Google Scholar
Chappellear, J. E. 1961 Direct numerical calculation of wave properties. J. Geophys. Res. 66, 501508.Google Scholar
Chen, B. & Saffman, P. G. 1980 Numerrical evidence for the existence of new types of gravity-waves of permanent form on deep-water. Stud. Appl. Maths 62, 121.Google Scholar
Cokelet, E. D. 1977 Steep gravity waves in water of arbitrary uniform depth. Phil. Trans. R. Soc. A 286, 183220.Google Scholar
De, S. C. 1955 Contributions to the theroy of Stokes waves. Proc. Camb. Phil. Soc. 51, 713736Google Scholar
Dixon, A. 1989 Momentum disturbances and wave trains. J. Fluid Mech 207, 295310.Google Scholar
Dold, J. W. & Peregrine, D. H. 1986 An efficient boundary-integral method for steep unsteady water waves. In Numerical Methods for Fluid Dynamics II (ed. K. W. Morton & M. J. Baines), pp. 671679.
Doole, S. H. 1994 Steady gravity waves on flows vorticity: bifurcatiom theory and variational principles. DPhil thesis, Oxford University, UK.
Fenton, J. D. 1979 A high-order cnoidal wave theory. J. Fluid Mech. 94, 129161.Google Scholar
Ferton, J. D. 1985 A fifth order Stokes theory for steady waves. J. Waterway, Port, Coastal, Oceam Engng Div. ASCE 111, 216234.Google Scholar
Jillians, W. J. 1989 The superhamonic insrability of Stokes’ waves in deep water. J. Fluid Mech. 204, 563579.Google Scholar
Jones, M. C. W. & Toland, J. F. 1985 The bifurcation and secondary bifurcation of capillary-gravity waves. Proc. R. Soc. Lond. A 399, 391417.Google Scholar
Jones, M. C. W. & Toland, J. F. 1986 Symmetry and the bifurcation of capillary-gravity waves. Arch. Rat. Mech. Anal. 96, 2953.Google Scholar
Keady, G. & Norbury, J. 1975 Water waves and conjugate streams. J. Fluid Mech. 70, 663671.Google Scholar
Keady, G. & Norbury, J 1978 Waves and conjugate steams with vorticity. Mathematika 25, 129150.Google Scholar
Kelvin, Lord 1886 On stationary waves in flowing water II. Phill. Mag 5, 445452.Google Scholar
Lokguet-Higgins, M. S. 1975 Integral properties of periodic gravity waves of finite amplitude. Proc. R. Soc. Lond. A 342, 157174.Google Scholar
Longuet-Higgins, M. S. & Fox, M. J. H. 1978 Theory of the almost largest wave. Part 2. Matching and analytic extension. J. Fluid Mech. 85, 769786.Google Scholar
Mielke, A. 1991 Hamiltonian and lagrangian flow on Center Manifolds with Applications to Elliptic Variational Problems. Lecture Notes in Mathematics, Vol. 1489, Springer.
Olver, P. J. 1982 A nonlinear Hamiltonian structure for the Euler eruations. J. Math. Anal. Appl. 89, 233250.Google Scholar
Radder, A. C. 1992 An explicit Hamiltonian formulation of surface waves in water of finite depth. J. Fluid Mech 237, 435455.Google Scholar
Schwartz, L. W. 1974 Computer extension and analytic continution of Stokes’ expansion for gravity waves. J. Fluid Mech. 62, 553578.Google Scholar
Tanaka, M. 1985 The stability of steady gravity waves. Part 2. J. Fluid Mech. 156, 281289.Google Scholar
Tanaka, M. 1986 The stability of solitary waves. Phys. Fluids 29, 650655.Google Scholar
Teles, Da Silva, A. F. T. & Peregrine, D. H. 1988 Steep, steady surface waves in water of finite depth with constant vorticity. J. Fluid Mech 195, 281302.Google Scholar
Ursell, F. 1953 The long wave paradox in the theory of gravity waves. Proc, Camb. Phil. Soc. 49, 685694.Google Scholar
Williams, J. M. 1981 Limiting gravity waves in water of finite depth. Phil. Trans. R. Soc. Lond. A 302, 139188.Google Scholar