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arXiv · cond-mat/9810251

Randomly Driven Granular Fluids: large scale structure

T. P. C. van Noije·M. H. Ernst·E. Trizac·I. Pagonabarraga
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Abstract

The nonequilibrium steady state of a granular fluid, driven by a random external force, is demonstrated to exhibit long range correlations, which behave as $\sim 1/r$ in three and $\sim \ln(L/r)$ in two dimensions. We calculate the corresponding structure factors over the whole range of wave numbers, and find good agreement with two-dimensional molecular dynamics simulations. It is also shown by means of a mode coupling calculation, how the mean field values for the steady state temperature and collision frequency, as obtained from the Enskog-Boltzmann equation, are renormalized by long wavelength hydrodynamic fluctuations.

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T. P. C. van Noije, M. H. Ernst, E. Trizac, I. Pagonabarraga. 1998-10-20. Randomly Driven Granular Fluids: large scale structure. https://doi.org/10.1103/physreve.59.4326

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