Hostname: page-component-cd9895bd7-hc48f Total loading time: 0 Render date: 2024-12-30T23:16:47.341Z Has data issue: false hasContentIssue false

A variational approach to Boussinesq modelling of fully nonlinear water waves

Published online by Cambridge University Press:  03 August 2010

GERT KLOPMAN*
Affiliation:
Applied Analysis and Mathematical Physics, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
BRENNY VAN GROESEN
Affiliation:
Applied Analysis and Mathematical Physics, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
MAARTEN W. DINGEMANS
Affiliation:
Delft Hydraulics, Boomkensdiep 11, 8303 KW Emmeloord, The Netherlands
*
Email address for correspondence: [email protected]

Abstract

In this paper we present a new method to derive Boussinesq-type equations from a variational principle. These equations are valid for nonlinear surface-water waves propagating over bathymetry. The vertical structure of the flow, required in the Hamiltonian, is approximated by a (series of) vertical shape functions associated with unknown parameter(s). It is not necessary to make approximations with respect to the nonlinearity of the waves. The resulting approximate Hamiltonian is positive definite, contributing to the good dynamical behaviour of the resulting equations. The resulting flow equations consist of temporal equations for the surface elevation and potential, as well as a (set of) elliptic equations for some auxiliary parameter(s). All equations only contain low-order spatial derivatives and no mixed time–space derivatives. Since one of the parameters, the surface potential, can be associated with a uniform shape function, the resulting equations are very well suited for wave–current interacting flows.

The variational method is applied to two simple models, one with a parabolic vertical shape function and the other with a hyperbolic-cosine vertical structure. For both, as well as the general series model, the flow equations are derived. Linear dispersion and shoaling are studied using the average Lagrangian. The model with a parabolic vertical shape function has improved frequency dispersion, as compared to classical Boussinesq models. The model with a hyperbolic-cosine vertical structure can be made to have exact phase and group velocity, as well as shoaling, for a certain frequency.

For the model with a parabolic vertical structure, numerical computations are done with a one-dimensional pseudo-spectral code. These show the nonlinear capabilities for periodic waves over a horizontal bed and an underwater bar. Further some long-distance computations for soliton wave groups over bathymetry are presented.

Type
Papers
Copyright
Copyright © Cambridge University Press 2010

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

REFERENCES

Agnon, Y., Madsen, P. A. & Schäffer, H. A. 1999 A new approach to high-order Boussinesq models. J. Fluid Mech. 399, 319333.CrossRefGoogle Scholar
Benjamin, T. B. 1984 Impulse, flow force and variational principles. IMA J. Appl. Math. 32 (1–3), 368 (with errata in the preamble of the same issue).CrossRefGoogle Scholar
Benjamin, T. B. & Feir, J. E. 1967 The disintegration of wave trains on deep water. Part 1. Theory. J. Fluid Mech. 27 (3), 417430.CrossRefGoogle Scholar
Benjamin, T. B. & Olver, P. J. 1982 Hamiltonian structure, symmetries and conservation laws for water waves. J. Fluid Mech. 125, 137185.CrossRefGoogle Scholar
Boussinesq, J. 1872 Théorie des ondes et des remous qui se propagent le long d'un canal rectangulaire horizontal, en communiquant au liquide contenu dans ce canal des vitesses sensiblement pareilles de la surface au fond. J. Math. Pure. Appl., Deuxième Sér. 17, 55108.Google Scholar
Bretherton, F. P. 1968 Propagation in slowly varying waveguides. Proc. R. Soc. Lond. A 302 (1471), 555576.Google Scholar
Brizard, A. J. 2005 Noether methods for fluids and plasmas. J. Plasma Phys. 71 (2), 225236.CrossRefGoogle Scholar
Broer, L. J. F. 1974 On the Hamiltonian theory of surface waves. Appl. Sci. Res. 29, 430446.CrossRefGoogle Scholar
Broer, L. J. F. 1975 Approximate equations for long wave equations. Appl. Sci. Res. 31 (5), 377395.CrossRefGoogle Scholar
Broer, L. J. F., van Groesen, E. W. C. & Timmers, J. M. W. 1976 Stable model equations for long water waves. Appl. Sci. Res. 32 (6), 619636.CrossRefGoogle Scholar
Chen, Y. & Liu, P. L.-F. 1995 Modified Boussinesq equations and associated parabolic models for water wave propagation. J. Fluid Mech. 288, 351381.CrossRefGoogle Scholar
Dingemans, M. W. 1994 Comparison of Computations With Boussinesq-Like Models and Laboratory Measurements. MAST-G8M note, H1684. Delft Hydraulics, 32 pp.Google Scholar
Dingemans, M. W. 1997 Water Wave Propagation Over Uneven Bottoms. Advanced Series on Ocean Engineering, vol. 13. World Scientific, 2 Parts, 967 pp.CrossRefGoogle Scholar
Dingemans, M. W. & Klopman, G. 2009 Effects of normalization and mild-slope approximation on wave reflection by bathymetry in a Hamiltonian wave model. In Proceedings of Twenty-Fourth International Workshop on Water Waves and Floating Bodies, Zelenogorsk, Russia.Google Scholar
Dingemans, M. W. & Otta, A. K. 2001 Nonlinear modulation of water waves. In Advances in Coastal and Ocean Engineering (ed. Liu, P. L.-F.), vol. 7, pp. 176. World Scientific.Google Scholar
Djordjević, V. D. & Redekopp, L. G. 1978 On the development of packets of surface gravity waves moving over an uneven bottom. J. Appl. Math. Phys. (ZAMP) 29, 950962.CrossRefGoogle Scholar
Dommermuth, D. G. & Yue, D. K. P. 1987 A high-order spectral method for the study of nonlinear gravity waves. J. Fluid Mech. 184, 267288.CrossRefGoogle Scholar
Fuhrman, D. R. & Bingham, H. B. 2004 Numerical solutions of fully nonlinear and highly dispersive Boussinesq equations in two horizontal dimensions. Intl J. Numer. Methods Fluids 44 (3), 231255.CrossRefGoogle Scholar
van Groesen, E. & Westhuis, J. H. 2002 Modelling and simulation of surface water waves. Math. Comput. Sim. 59 (4), 341360.CrossRefGoogle Scholar
Hayes, W. D. 1970 a Conservation of action and modal wave action. Proc. R. Soc. Lond. A 330 (1541), 187208.Google Scholar
Hayes, W. D. 1970 b Kinematic wave theory. Proc. R. Soc. Lond. A 330 (1541), 209226.Google Scholar
Hayes, W. D. 1973 Group velocity and nonlinear dispersive wave propagation. Proc. R. Soc. Lond. A 332 (1589), 199221.Google Scholar
Hsiao, S.-C., Lynett, P., Hwung, H.-H. & Liu, P. L.-F. 2005 Numerical simulations of nonlinear short waves using a multilayer model. J. Engng Mech. 131 (3), 231243.Google Scholar
Katopodes, N. D. & Dingemans, M. W. 1989 Hamiltonian approach to surface wave models. In Computational Modelling and Experimental Methods in Hydraulics (HYDROCOMP '89), Dubrovnik, Yugoslavia (ed. Maksimovič, Č. & Radojkovič, M.), pp. 137147. Elsevier.Google Scholar
Klopman, G., Dingemans, M. W. & van Groesen, E. 2005 A variational model for fully nonlinear water waves of Boussinesq type. In Proceedigs of Twentieth International Workshop on Water Waves and Floating Bodies, Longyearbyen, Spitsbergen, Norway.Google Scholar
Liu, P. L.-F. 1989 A note on long waves induced by short-wave groups over a shelf. J. Fluid Mech. 205, 163170.CrossRefGoogle Scholar
Ludwig, D. 1970 Modified W.K.B. method for coupled ionospheric equations. J. Atmos. Terr. Phys. 32 (6), 991998.CrossRefGoogle Scholar
Luth, H. R., Klopman, G. & Kitou, N. 1994 Project 13g: kinematics of waves breaking partially on an offshore bar. LDV measurements for waves with and without a net onshore current. Tech. Rep. H1573. Delft Hydraulics, Delft, The Netherlands, 40 pp.Google Scholar
Lynett, P. J. & Liu, P. L.-F. 2004 a A two-layer approach to wave modelling. Proc. R. Soc. Lond. A 460 (2049), 26372669.CrossRefGoogle Scholar
Lynett, P. J. & Liu, P. L.-F. 2004 b Linear analysis of the multi-layer model. Coast. Engng 51 (5–6), 439454.CrossRefGoogle Scholar
Madsen, P. A., Bingham, H. B. & Schäffer, H. A. 2003 Boussinesq-type formulations for fully nonlinear and extremely dispersive water waves: derivation and analysis. Proc. R. Soc. Lond. A 459, 10751104.CrossRefGoogle Scholar
Madsen, P. A., Murray, R. & Sørensen, O. R. 1991 A new form of the Boussinesq equations with improved linear dispersion characteristics. Coast. Engng 15 (4), 371388.CrossRefGoogle Scholar
Madsen, P. A. & Sørensen, O. R. 1992 A new form of the Boussinesq equations with improved linear dispersion characteristics. Part 2. A slowly-varying bathymetry. Coast. Engng 18 (3–4), 183204.CrossRefGoogle Scholar
Mei, C. C. & Benmoussa, C. 1984 Long waves induced by short-wave groups over an uneven bottom. J. Fluid Mech. 139, 219235.CrossRefGoogle Scholar
Milder, D. M. 1977 A note on: ‘On Hamilton's principle for surface waves’. J. Fluid Mech. 83 (1), 159161.CrossRefGoogle Scholar
Milder, D. M. 1990 The effect of truncation on surface-wave Hamiltonians. J. Fluid Mech. 216, 249262.CrossRefGoogle Scholar
Miles, J. W. 1977 On Hamilton's principle for surface waves. J. Fluid Mech. 83 (1), 153158.CrossRefGoogle Scholar
Otta, A. K., Dingemans, M. W. & Radder, A. C. 1996 A Hamiltonian model for nonlinear water waves and its applications. In Proceedings of 25th International Conference Coastal Engineering, Orlando, vol. 1, pp. 11561167. ASCE, New York.Google Scholar
Radder, A. C. 1992 An explicit Hamiltonian formulation of surface waves in water of finite depth. J. Fluid Mech. 237, 435455.CrossRefGoogle Scholar
Radder, A. C. 1999 Hamiltonian dynamics of water waves. In Advance in Coastal and Ocean Engineering (ed. Liu, P. L.-F.), vol. 4, pp. 2159. World Scientific.CrossRefGoogle Scholar
Rienecker, M. M. & Fenton, J. D. 1981 A Fourier approximation method for steady water waves. J. Fluid Mech. 104, 119137.CrossRefGoogle Scholar
Shepherd, T. G. 1990 Symmetries, conservation laws, and Hamiltonian structure in geophysical fluid dynamics. Adv. Geophys. 32, 287338.CrossRefGoogle Scholar
Turpin, F.-M., Benmoussa, C. & Mei, C. C. 1983 Effects of slowly varying depth and current on the evolution of a Stokes wavepacket. J. Fluid Mech. 132, 123.CrossRefGoogle Scholar
West, B. J., Brueckner, K. A., Janda, R. S., Milder, D. M. & Milton, R. L. 1987 A new numerical method for surface hydrodynamics. J. Geophys. Res. 92 (C11), 1180311824.CrossRefGoogle Scholar
Westhuis, J.-H. 2001 The numerical simulation of nonlinear waves in a hydrodynamic model test basin. PhD thesis, University of Twente, Enschede, The Netherlands.Google Scholar
Whitham, G. B. 1967 Variational methods and applications to water waves. Proc. R. Soc. Lond. A 299 (1456), 625.Google Scholar
Whitham, G. B. 1974 Linear and Nonlinear Waves. Wiley Interscience.Google Scholar
Witting, J. M. 1984 A unified model for the evolution of nonlinear water waves. J. Comput. Phys. 56 (4), 203236.CrossRefGoogle Scholar
Zakharov, V. E. 1968 Stability of periodic waves of finite amplitude on the surface of a deep fluid. J. Appl. Mech. Technol. Phys. 9 (2), 190194 (originally published in Z. Prildadnoi Mekh. Tekh. Fiz. 9 (2), pp. 86–94, 1968).CrossRefGoogle Scholar