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arXiv · 2507.19972

Eulerian-Lagrangian scaling of the Lyapunov exponent in homogeneous turbulence

Jin Ge·Joran Rolland·John Christos Vassilicos
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Abstract

We present a heuristic derivation of the maximal Lyapunov exponent $\gamma$ of homogeneous turbulence which yields two new relations, a sweeping relation and the scaling of the uncertainty field's integral length $L_{\Delta}$. These relations and the maximal Lyapunov exponent's scaling that they imply are confirmed by periodic turbulence simulations. As the Reynolds number $Re_\lammbda$ increases, $L_\Delta$ and $\gamma^{-1}$ decrease towards values smaller than the Kolmogorov length and time scales.

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Jin Ge, Joran Rolland, John Christos Vassilicos. 2025-07-26. Eulerian-Lagrangian scaling of the Lyapunov exponent in homogeneous turbulence. https://doi.org/10.1103/zv93-zkkv

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