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arXiv · 1502.05358

Angular multiscale statistics of Lagrangian trajectories in turbulence

Wouter Bos·Benjamin Kadoch·Kai Schneider
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Abstract

The angle between subsequent particle displacement increments is evaluated as a function of the timelag in isotropic turbulence. It is shown that the evolution of this angle contains two well-defined power-laws, reflecting the multi-scale dynamics of high-Reynolds number turbulence. The proba-bility density function of the directional change is shown to be self-similar and well approximated by an analytically derived model assuming Gaussianity and independence of the velocity and the Lagrangian acceleration.

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Wouter Bos, Benjamin Kadoch, Kai Schneider. 2014-11-20. Angular multiscale statistics of Lagrangian trajectories in turbulence. https://arxiv.org/abs/1502.05358

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