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Symmetric three-particle motion in Stokes flow: equilibrium for heavy spheres in contrast to "end-of-world" for point forces

Maria L. Ekiel-Jezewska·Eligiusz Wajnryb
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Abstract

A stationary stable solution of the Stokes equations for three identical heavy solid spheres falling in a vertical plane is found. It has no analog in the point-particle approximation. Three spheres aligned horizontally at equal distances evolve towards the equilibrium relative configuration while the point particles collapse onto a single point in a finite time.

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Maria L. Ekiel-Jezewska, Eligiusz Wajnryb. 2005-08-21. Symmetric three-particle motion in Stokes flow: equilibrium for heavy spheres in contrast to "end-of-world" for point forces. https://doi.org/10.1103/physreve.73.046309

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