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arXiv · 1010.3422

Tracking the dynamics of translation and absolute orientation of a sphere in a turbulent flow

Robert Zimmermann·Yoann Gasteuil·Mickael Bourgoin·Romain Volk·Alain Pumir·Jean-François Pinton
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Abstract

We study the 6-dimensional dynamics -- position and orientation -- of a large sphere advected by a turbulent flow. The movement of the sphere is recorded with 2 high-speed cameras. Its orientation is tracked using a novel, efficient algorithm; it is based on the identification of possible orientation `candidates' at each time step, with the dynamics later obtained from maximization of a likelihood function. Analysis of the resulting linear and angular velocities and accelerations reveal a surprising intermittency for an object whose size lies in the integral range, close to the integral scale of the underlying turbulent flow.

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Robert Zimmermann, Yoann Gasteuil, Mickael Bourgoin, Romain Volk, Alain Pumir, Jean-François Pinton. 2010-10-17. Tracking the dynamics of translation and absolute orientation of a sphere in a turbulent flow. https://doi.org/10.1063/1.3554304

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