On the well-possedness of time-dependent three-dimensional Euler fluid flows

Miroslav Bulíček; Josef Málek

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arXiv · 2408.09573

On the well-possedness of time-dependent three-dimensional Euler fluid flows

Miroslav Bulíček·Josef Málek

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Abstract

We study the mathematical properties of time-dependent flows of incompressible fluids that respond as an Euler fluid until the modulus of the symmetric part of the velocity gradient exceeds a certain, a-priori given but arbitrarily large, critical value. Once the velocity gradient exceeds this threshold, a dissipation mechanism is activated. Assuming that the fluid, after such an activation, dissipates the energy in a specific manner, we prove that the corresponding initial-boundary-value problem is globally-in-time well-posed in the sense of Hadamard. In particular, we show that for an arbitrary, sufficiently regular, initial velocity there is a unique weak solution to the spatially periodic problem.

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Miroslav Bulíček, Josef Málek. 2024-08-18. On the well-possedness of time-dependent three-dimensional Euler fluid flows. https://arxiv.org/abs/2408.09573

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