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arXiv · 2209.02666

Vanishing viscosity limit for concentrated vortex rings

Paolo Buttà·Guido Cavallaro·Carlo Marchioro
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Abstract

We study the time evolution of a viscous incompressible fluid with axial symmetry without swirl, when the initial vorticity is very concentrated in $N$ disjoint rings. We show that in a suitable joint limit, in which both the thickness of the rings and the viscosity tend to zero, the vorticity remains concentrated in $N$ disjointed rings, each one of them performing a simple translation along the symmetry axis with constant speed.

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Paolo Buttà, Guido Cavallaro, Carlo Marchioro. 2022-09-06. Vanishing viscosity limit for concentrated vortex rings. https://doi.org/10.1063/5.0124516

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