Small moving rigid body into a viscous incompressible fluid

Christophe Lacave; Takéo Takahashi

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arXiv · 1506.08964

Small moving rigid body into a viscous incompressible fluid

Christophe Lacave·Takéo Takahashi

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Abstract

We consider a single disk moving under the influence of a 2D viscous fluid and we study the asymptotic as the size of the solid tends to zero.If the density of the solid is independent of $\varepsilon$, the energy equality is not sufficient to obtain a uniform estimate for the solid velocity. This will be achieved thanks to the optimal $L^p-L^q$ decay estimates of the semigroup associated to the fluid-rigid body system and to a fixed point argument. Next, we will deduce the convergence to the solution of the Navier-Stokes equations in $\R^2$.

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Christophe Lacave, Takéo Takahashi. 2015-06-30. Small moving rigid body into a viscous incompressible fluid. https://arxiv.org/abs/1506.08964

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