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arXiv · 1608.02889

Localized shear generates three-dimensional transport

Lachlan D. Smith·Murray Rudman·Daniel R. Lester·Guy Metcalfe
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Abstract

Understanding the mechanisms that control three-dimensional (3D) fluid transport is central to many processes including mixing, chemical reaction and biological activity. Here a novel mechanism for 3D transport is uncovered where fluid particles are kicked between streamlines near a localized shear, which occurs in many flows and materials. This results in 3D transport similar to Resonance Induced Dispersion (RID); however, this new mechanism is more rapid and mutually incompatible with RID. We explore its governing impact with both an abstract 2-action flow and a model fluid flow. We show that transitions from one-dimensional (1D) to two-dimensional (2D) and 2D to 3D transport occur based on the relative magnitudes of streamline jumps in two transverse directions.

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Lachlan D. Smith, Murray Rudman, Daniel R. Lester, Guy Metcalfe. 2016-08-09. Localized shear generates three-dimensional transport. https://doi.org/10.1063/1.4979666

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