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arXiv · 2505.22700

The early stage of the motion along the gradient of a concentrated vortex structure

Franco Flandoli·Matteo Palmieri·Milo Viviani
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Abstract

We give a rigorous mathematical result, supported by numerical simulations, of the aggregation of a concentrated vortex blob with an underlying non-constant vorticity field: the blob moves in the direction of the gradient of the field. It is a unique example of a Lagrangian explanation of aggregation of vortex structures of the same sign in 2D inviscid fluids. The result is also extended to almost vertical vortex filaments in a (possibly thin) three-dimensional domain.

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Franco Flandoli, Matteo Palmieri, Milo Viviani. 2025-05-28. The early stage of the motion along the gradient of a concentrated vortex structure. https://arxiv.org/abs/2505.22700

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