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arXiv · 2305.15356

Time-zero limits of Kaden's spirals and 2D Euler

Bartosz Bieganowski·Tomasz Cieślak·Jakub Siemianowski
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Abstract

The present note is devoted to the studies of the relation of the time-zero limits of Kaden's spirals and the 2D Euler equation. It is shown that the time-zero limits of Kaden's spirals satisfy inhomogeneous 2D Euler in a weak sense. As a corollary, the necessity of both, the decay of spherical averages around the origin of the spiral as well as the velocity matching condition, for the 2D Euler equation to hold in a weak sense, is shown. Finally, some preliminary results concerning the Kaden spirals are obtained.

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Bartosz Bieganowski, Tomasz Cieślak, Jakub Siemianowski. 2023-05-24. Time-zero limits of Kaden's spirals and 2D Euler. https://arxiv.org/abs/2305.15356

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