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The Stability Balloon for Two-dimensional Vortex Ripple Patterns

J. L. Hansen·M. van Hecke·C. Ellegaard·K. H. Andersen·T. Bohr·A. Haaning·T. Sams
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Abstract

Patterns of vortex ripples form when a sand bed is subjected to an oscillatory fluid flow. Here we describe experiments on the response of regular vortex ripple patterns to sudden changes of the driving amplitude a or frequency f. A sufficient decrease of f leads to a "freezing" of the pattern, while a sufficient increase of f leads to a supercritical secondary "pearling" instability. Sufficient changes in the amplitude a lead to subcritical secondary "doubling" and "bulging" instabilities. Our findings are summarized in a "stability balloon" for vortex ripple pattern formation.

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J. L. Hansen, M. van Hecke, C. Ellegaard, K. H. Andersen, T. Bohr, A. Haaning, T. Sams. 2001-06-22. The Stability Balloon for Two-dimensional Vortex Ripple Patterns. https://doi.org/10.1103/physrevlett.87.204301

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