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arXiv · 1401.0678

Velocity-Gradient Probability Distribution Functions in a Lagrangian Model of Turbulence

L. Moriconi·R. M. Pereira·L. S. Grigorio
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Abstract

The Recent Fluid Deformation Closure (RFDC) model of lagrangian turbulence is recast in path-integral language within the framework of the Martin-Siggia-Rose functional formalism. In order to derive analytical expressions for the velocity-gradient probability distribution functions (vgPDFs), we carry out noise renormalization in the low-frequency regime and find approximate extrema for the Martin-Siggia-Rose effective action. We verify, with the help of Monte Carlo simulations, that the vgPDFs so obtained yield a close description of the single-point statistical features implied by the original RFDC stochastic differential equations.

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L. Moriconi, R. M. Pereira, L. S. Grigorio. 2014-01-03. Velocity-Gradient Probability Distribution Functions in a Lagrangian Model of Turbulence. https://doi.org/10.1088/1742-5468/2014/10/p10015

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