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Intermittency in the Enstrophy Cascade of Two-dimensional Fully-developed Turbulence: Universal Features

Bhimsen K. Shivamoggi
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Abstract

Intermittency (externally induced) in the two-dimensional (2D) enstrophy cascade is shown to be able to maintain a finite enstrophy along with a vorticity conservation anomaly. Intermittency mechanisms of three-dimensional (3D) energy cascade and 2D enstrophy cascade in fully-developed turbulence (FDT) seem to have some universal features. The parabolic-profile approximation (PPA) for the singularity spectrum f(a) in multi-fractal model is used and extended to the appropriate microscale regimes to exhibit these features. The PPA is also shown to afford, unlike the generic multi-fractal model, an analytical calculation of probability distribution functions (PDF) of flow-variable gradients in these FDT cases and to describe intermittency corrections that complement those provided by the homogeneous fractal model.

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Bhimsen K. Shivamoggi. 2007-02-28. Intermittency in the Enstrophy Cascade of Two-dimensional Fully-developed Turbulence: Universal Features. https://arxiv.org/abs/physics/0410109

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