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arXiv · 1701.07094

Quantifying the role of folding in nonautonomous flows: the unsteady Double-Gyre

K. G. D. Sulalitha Priyankara·Sanjeeva Balasuriya·Erik Bollt
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Abstract

We analyze chaos in the well-known nonautonomous Double-Gyre system. A key focus is on folding, which is possibly the less-studied aspect of the "stretching + folding = chaos" mantra of chaotic dynamics. Despite the Double-Gyre not having the classical homoclinic structure for the usage of the Smale-Birkhoff theorem to establish chaos, we use the concept of folding to prove the existence of an embedded horseshoe-map. We also show how curvature of manifolds can be used to identify fold points in the Double-Gyre. This method is applicable to general nonautonomous flows in two dimensions, defined for either finite or infinite times.

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K. G. D. Sulalitha Priyankara, Sanjeeva Balasuriya, Erik Bollt. 2017-01-24. Quantifying the role of folding in nonautonomous flows: the unsteady Double-Gyre. https://doi.org/10.1142/s0218127417501565

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