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arXiv · 1404.0652

Velocity Reversal Criterion of a Body Immersed in a Sea of Particles

Xuwen Chen·Walter Strauss
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Abstract

We consider a rigid body colliding with a continuum of particles. We assume that the body is moving at a velocity close to an equilibrium velocity V_{\infty} and that the particles colliding with the body reflect diffusely, that is, probabilistically with some probablility distribution K. We find a condition that is sufficient and almost necessary that the collective force of the colliding particles reverses the relative velocity V(t) of the body, that is, changes the sign of V(t)-V_{\infty}, before the body approaches equilibrium. Examples of both reversal and irreversal are given. This is in strong contrast with the pure specular reflection case in which only reversal happens.

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Xuwen Chen, Walter Strauss. 2014-04-02. Velocity Reversal Criterion of a Body Immersed in a Sea of Particles. https://doi.org/10.1007/s00220-015-2368-y

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