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The dispersion relation for a nonlinear random gravity wave field

Published online by Cambridge University Press:  29 March 2006

Norden E. Huang
Affiliation:
NASA Wallops Flight Center, Wallops Island, Virginia 23337
Chi-Chao Tung
Affiliation:
Department of Civil Engineering, North Carolina State University, Raleigh

Abstract

The dispersion relation for a random gravity wave field is derived using the complete system of nonlinear equations. It is found that the generally accepted dispersion relation is only a first-order approximation to the mean value. The correction to this approximation is expressed in terms of the energy spectral function of the wave field. The non-zero mean deviation is proportional to the ratio of the mean Eulerian velocity at the surface and the local phase velocity. In addition to the mean deviation, there is a random scatter. The root-mean-square value of this scatter is proportional to the ratio of the root-mean-square surface velocity and the local phase velocity. As for the phase velocity, the nonzero mean deviation is equal to the mean Eulerian velocity while the root-mean-square scatter is equal to the root-mean-square surface velocity. Special cases are considered and a comparison with experimental data is also discussed.

Type
Research Article
Copyright
© 1976 Cambridge University Press

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References

Grose, P. L., Warsh, K. L. & Garstang, M. 1972 Dispersion relations and wave shapes J. Geophys. Res. 77, 39023906.Google Scholar
Huang, N. E. 1971 Derivation of Stokes drift for a deep-water random gravity wave field Deep-Sea Res. 18, 255259.Google Scholar
Longuet-Higgins, M. S. 1962 Resonant interactions between two trains of gravity waves J. Fluid Mech. 12, 321332.Google Scholar
Longuet-Higgins, M. S., Cartwright, D. E. & Smith, N. D. 1963 Observations of the directional spectrum of sea waves using the motions of a floating buoy. In Ocean Wave Spectra, pp. 111136. Prentice-Hall.
Longuet-Higgins, M. S. & Phillips, O. M. 1962 Phase velocity effects in tertiary wave interactions J. Fluid Mech. 12, 333336.Google Scholar
Phillips, O. M. 1958 The equilibrium range in the spectrum of wind generated waves J. Fluid Mech. 4, 426434.Google Scholar
Phillips, O. M. 1960a On the dynamics of unsteady gravity waves of finite amplitude. Part 1 J. Fluid Mech. 9, 193217.Google Scholar
Phillips, O. M. 1960b The mean horizontal momentum and surface velocity of finiteamplitude random gravity waves J. Geophys. Res. 65, 34733476.Google Scholar
Phillips, O. M. 1966 The Dynamics of the Upper Ocean. Cambridge University Press.
Stokes, G. G. 1847 On the theory of oscillatory waves Trans. Camb. Phil. Soc. 8, 441455.Google Scholar
Willebrand, J. 1975 Energy transport in a nonlinear and inhomogeneous random gravity wave field J. Fluid Mech. 70, 113126.Google Scholar
Wright, J. W. & Keller, W. C. 1970 Doppler spectra in microwave scattering from wind waves Phys. Fluids, 14, 466474.Google Scholar
Yefijmov, V. V. & Khristoforov, G. N. 1971 Wave-related and turbulent components of velocity spectrum in the top sea layer Izv. Atmos. Ocean. Phys. 7, 200211.Google Scholar
Yefimov, V. V., SOLOV'YEV, YU. P. & Khristoforov, G. N. 1972 Observational determination of the phase velocities of spectral components of wind waves Izv. Atmos. Ocean. Phys. 8, 435446.Google Scholar