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arXiv · 0710.3379

Asymptotic description of solitary wave trains in fully nonlinear shallow-water theory

G. A. El·R. H. J. Grimshaw·N. F. Smyth
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Abstract

We derive an asymptotic formula for the amplitude distribution in a fully nonlinear shallow-water solitary wave train which is formed as the long-time outcome of the initial-value problem for the Su-Gardner (or one-dimensional Green-Naghdi) system. Our analysis is based on the properties of the characteristics of the associated Whitham modulation system which describes an intermediate "undular bore" stage of the evolution. The resulting formula represents a "non-integrable" analogue of the well-known semi-classical distribution for the Korteweg-de Vries equation, which is usually obtained through the inverse scattering transform. Our analytical results are shown to agree with the results of direct numerical simulations of the Su-Gardner system. Our analysis can be generalised to other weakly dispersive, fully nonlinear systems which are not necessarily completely integrable.

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BibTeXRIS

G. A. El, R. H. J. Grimshaw, N. F. Smyth. 2007-10-18. Asymptotic description of solitary wave trains in fully nonlinear shallow-water theory. https://doi.org/10.1016/j.physd.2008.03.031

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