Distribution of Brownian particles in turbulence

Itzhak Fouxon; Eugene Mednikov

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arXiv · 1110.5073

Distribution of Brownian particles in turbulence

Itzhak Fouxon·Eugene Mednikov

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Abstract

We consider Brownian particles immersed in the fluid which flow is turbulent. We study the limit where the particles' inertia is weak and their velocity relaxes fast to the velocity of the flow. The trajectories of the particles in this case have a strange attractor in the physical space, if the particles' diffusion is neglected. Under the latter condition the singular density of the particles was recently described completely. The analysis was done for real turbulence and did not involve the flow modeling. Here we take the diffusion into account showing how it modifies the statistics. The analysis is performed also for real turbulence. Experimentally testable predictions are made.

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Itzhak Fouxon, Eugene Mednikov. 2011-10-23. Distribution of Brownian particles in turbulence. https://arxiv.org/abs/1110.5073

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