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arXiv · 1202.0350

Chaotic mixing and fractals in a geophysical jet current

M. V. Budyansky·S. V. Prants
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Abstract

We model Lagrangian lateral mixing and transport of passive scalars in meandering oceanic jet currents by two-dimensional advection equations with a kinematic stream function with a time-dependent amplitude of a meander imposed. The advection in such a model is known to be chaotic in a wide range of the meander's characteristics. We study chaotic transport in a stochastic layer and show that it is anomalous. The geometry of mixing is examined and shown to be fractal-like. The scattering characteristics (trapping time of advected particles and the number of their rotations around elliptical points) are found to have a hierarchical fractal structure as functions of initial particle's positions. A correspondence between the evolution of material lines in the flow and elements of the fractal is established.

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M. V. Budyansky, S. V. Prants. 2012-02-02. Chaotic mixing and fractals in a geophysical jet current. https://doi.org/10.1016/j.cnsns.2006.05.004

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