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arXiv · 1704.01042

Chaotic properties of a turbulent isotropic fluid

A. Berera·R. D. J. G. Ho
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Abstract

By tracking the divergence of two initially close trajectories in phase space in an Eulerian approach to forced turbulence, the relation between the maximal Lyapunov exponent $λ$, and the Reynolds number $Re$ is measured using direct numerical simulations, performed on up to $2048^3$ collocation points. The Lyapunov exponent is found to solely depend on the Reynolds number with $λ\propto Re^{0.53}$ and that after a transient period the divergence of trajectories grows at the same rate at all scales. Finally a linear divergence is seen that is dependent on the energy forcing rate. Links are made with other chaotic systems.

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A. Berera, R. D. J. G. Ho. 2017-12-20. Chaotic properties of a turbulent isotropic fluid. https://doi.org/10.1103/physrevlett.120.024101

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