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Induced defect nucleation and side-band instabilities in hexagons with rotation and mean flow

Yuan-Nan Young·Hermann Riecke
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Abstract

The combined effect of mean flow and rotation on hexagonal patterns is investigated using Ginzburg-Landau equations that include nonlinear gradient terms as well as the nonlocal coupling provided by the mean flow. Long-wave and short-wave side-band instabilities are determined. Due to the nonlinear gradient terms and enhanced by the mean flow, the penta-hepta defects can become unstable to the induced nucleation of dislocations in the defect-free amplitude, which can lead to the proliferation of penta-hepta defects and persistent spatio-temporal chaos. For individual penta-hepta defects the nonlinear gradient terms enhance climbing or gliding motion, depending on whether they break the chiral symmetry or not.

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Yuan-Nan Young, Hermann Riecke. 2002-07-30. Induced defect nucleation and side-band instabilities in hexagons with rotation and mean flow. https://doi.org/10.1016/s0167-2789(02)00739-x

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