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arXiv · 1903.04890

What kinds of KdV-type equations are allowed by an uneven bottom

Anna Karczewska·Piotr Rozmej
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Abstract

In this study, we give a survey of derivations of KdV-type equations with an uneven bottom for several cases when small (perturbation) parameters $\alpha, \beta, \delta$ are of different orders. Six different cases of such ordering are discussed. Surprisingly, for all these cases the Boussinesq equations can be made compatible only for the particular piecewise linear bottom profiles, and the correction function has a universal form. For such bottom relief, several new KdV-type wave equations are derived. These equations generalize the KdV, the extended KdV (KdV2), the fifth-order KdV (KdV5) and the Gardner equations.

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Anna Karczewska, Piotr Rozmej. 2019-03-07. What kinds of KdV-type equations are allowed by an uneven bottom. https://doi.org/10.1016/j.cnsns.2019.105073

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