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arXiv · 0811.4410

Acceleration statistics of finite-sized particles in turbulent flow: the role of Faxen forces

Enrico Calzavarini·Romain Volk·Mickael Bourgoin·Emmanuel Leveque·Jean-Francois Pinton·Federico Toschi
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Abstract

The dynamics of particles in turbulence when the particle-size is larger than the dissipative scale of the carrier flow is studied. Recent experiments have highlighted signatures of particles finiteness on their statistical properties, namely a decrease of their acceleration variance, an increase of correlation times -at increasing the particles size- and an independence of the probability density function of the acceleration once normalized to their variance. These effects are not captured by point particle models. By means of a detailed comparison between numerical simulations and experimental data, we show that a more accurate model is obtained once Faxen corrections are included.

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Enrico Calzavarini, Romain Volk, Mickael Bourgoin, Emmanuel Leveque, Jean-Francois Pinton, Federico Toschi. 2008-11-26. Acceleration statistics of finite-sized particles in turbulent flow: the role of Faxen forces. https://doi.org/10.1017/s0022112009006880

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