Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-09T07:04:01.982Z Has data issue: false hasContentIssue false

On wave scattering by random inhomogeneities, with application to the theory of weak bores

Published online by Cambridge University Press:  29 March 2006

M. S. Howe
Affiliation:
Imperial College, London, S.W. 7

Abstract

This paper considers the propagation and scattering of waves in dispersive and non-dispersive media containing random inhomogeneities. A detailed discussion of the propagation of the coherent component of the wave field is presented, and a rather general method for obtaining the absorption coefficient and scattering cross-section per unit volume of medium is described. A major objective is to derive macroscopic equations for the propagation of the coherent field in the sense that the damping due to scattering appears in the wave equation as pseudo-viscosity. The paper is concluded by a detailed application of the theory to the problem of the propagation of surface gravity waves over a stretch of shallow water with a ‘rough’ bed. By including finite amplitude effects a balance is achieved between the dispersion of the pseudo-viscous term and the non-linear convective terms, which enables the steady profile of a weak bore to be calculated.

Type
Research Article
Copyright
© 1971 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

Crow, S. C. 1969 J. Fluid Mech. 37, 529.
Ffowcs Williams, J. E. & Howe, M. S. 1971 To appear in J. Fluid Mech.
Hess, W. N. 1968 The Radiation Belt and Magnetosphere. Waltham, Mass: Blaisdell.
Howe, M. S. 1971 Wave propagation in random media J. Fluid Mech. 45, 769.Google Scholar
Karal, F. C. & Keller, J. B. 1964 J. Math. Phys. 5, 537.
Keller, J. B. 1964 Proc. Symp. appl. Math. 16, 145. Providence, R.I.: Amer. Math. Soc.
Lighthill, M. J. 1953 Proc. Camb. Phil. Soc. 49, 531.
Lighthill, M. J. 1956 Surveys in Mechanics (ed. G. K. Batchelor and R. M. Davies), pp. 250351. Cambridge University Press.
Lighthill, M. J. 1957 Naval Hydrodynamics, ch. 2. Washington, D.C.: Publ. 515, Nat. Acad. Sci., Nat. Res. Coun.
Stoker, J. J. 1957 Water Waves. New York: Interscience.