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arXiv · 2608.22380

A small rigid body immersed in a three-dimensional viscous fluid and the vanishing viscosity limit

Xiaoguang You
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Abstract

In this paper, we investigate the asymptotic behavior of a coupled fluid--rigid body system, consisting of a rigid body immersed in a three-dimensional viscous incompressible fluid, as the body size and the fluid viscosity vanish. We prove that the limiting velocity field is governed by the whole-space incompressible Euler equations. Moreover, the influence of the fluid on the rigid body motion is shown to vanish in this limit.

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Xiaoguang You. 2026-08-23. A small rigid body immersed in a three-dimensional viscous fluid and the vanishing viscosity limit. https://arxiv.org/abs/2608.22380

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