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arXiv · 1011.2476

Breakdown of self-similarity at the crests of large amplitude standing water waves

Jon Wilkening
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Abstract

We study the limiting behavior of large-amplitude standing waves on deep water using high-resolution numerical simulations in double and quadruple precision. While periodic traveling waves approach Stokes's sharply crested extreme wave in an asymptotically self-similar manner, we find that standing waves behave differently. Instead of sharpening to a corner or cusp as previously conjectured, the crest tip develops a variety of oscillatory structures. This causes the bifurcation curve that parametrizes these waves to fragment into disjoint branches corresponding to the different oscillation patterns that occur. In many cases, a vertical jet of fluid pushes these structures upward, leading to wave profiles commonly seen in wave tank experiments. Thus, we observe a rich array of dynamic behavior at small length scales in a regime previously thought to be self-similar.

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Jon Wilkening. 2011-10-26. Breakdown of self-similarity at the crests of large amplitude standing water waves. https://doi.org/10.1103/physrevlett.107.184501

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