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arXiv · 1602.04624

Diffusion of a Brownian ellipsoid in a force field

Erik Aurell·Stefano Bo·Marcelo Dias·Ralf Eichhorn·Raffaele Marino
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Abstract

We calculate the effective long-term convective velocity and dispersive motion of an ellipsoidal Brownian particle in three dimensions when it is subjected to a constant external force. This long-term motion results as a "net" average behavior from the particle rotation and translation on short time scales. Accordingly, we apply a systematic multi-scale technique to derive the effective equations of motion valid on long times. We verify our theoretical results by comparing them to numerical simulations.

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Erik Aurell, Stefano Bo, Marcelo Dias, Ralf Eichhorn, Raffaele Marino. 2016-02-15. Diffusion of a Brownian ellipsoid in a force field. https://doi.org/10.1209/0295-5075%2F114%2F30005

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