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arXiv · 2305.18162

Diffusion enhancement and Taylor dispersion for rotationally symmetric flows in discs and pipes

Michele Coti Zelati·Michele Dolce·Chia-Chun Lo
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Abstract

In this note, we study the long-time dynamics of passive scalars driven by rotationally symmetric flows. We focus on identifying precise conditions on the velocity field in order to prove enhanced dissipation and Taylor dispersion in three-dimensional infinite pipes. As a byproduct of our analysis, we obtain an enhanced decay for circular flows on a disc of arbitrary radius.

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Michele Coti Zelati, Michele Dolce, Chia-Chun Lo. 2023-05-29. Diffusion enhancement and Taylor dispersion for rotationally symmetric flows in discs and pipes. https://arxiv.org/abs/2305.18162

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