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arXiv · 0906.2755

Nonlocal Form of the Rapid Pressure-Strain Correlation in Turbulent Flows

Peter E. Hamlington·Werner J. A. Dahm
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Abstract

A new fundamentally-based formulation of nonlocal effects in the rapid pressure-strain correlation in turbulent flows has been obtained. The resulting explicit form for the rapid pressure-strain correlation accounts for nonlocal effects produced by spatial variations in the mean-flow velocity gradients, and is derived through Taylor expansion of the mean velocity gradients appearing in the exact integral relation for the rapid pressure-strain correlation. The integrals in the resulting series expansion are solved for high- and low-Reynolds number forms of the longitudinal correlation function $f(r)$, and the resulting nonlocal rapid pressure-strain correlation is expressed as an infinite series in terms of Laplacians of the mean strain rate tensor. The new formulation is used to obtain a nonlocal transport equation for the turbulence anisotropy that is expected to provide improved predictions of the anisotropy in strongly inhomogeneous flows.

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Peter E. Hamlington, Werner J. A. Dahm. 2009-06-15. Nonlocal Form of the Rapid Pressure-Strain Correlation in Turbulent Flows. https://doi.org/10.1103/physreve.80.046311

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