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arXiv · 1005.4108

Fluctuating hydrodynamics for dilute granular gases: a Monte Carlo study

Giulio Costantini·Andrea Puglisi
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Abstract

We investigate hydrodynamic noise in a dilute granular gas during the homogeneous cooling state, by means of a proper application of the Direct Simulation Monte Carlo (DSMC) algorithm. The DSMC includes a source of randomization which is not present in Molecular Dynamics (MD) for inelastic hard disks. Notwithstanding this difference, a fair quantitative agreement is found, including a violation of the fluctuation-dissipation relation for the noise amplitude of the same order observed in MD. This study suggests that deterministic collision dynamics is not an essential ingredient to reproduce, up to a good degree of approximation, hydrodynamic fluctuations in dilute granular gases.

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Giulio Costantini, Andrea Puglisi. 2010-05-22. Fluctuating hydrodynamics for dilute granular gases: a Monte Carlo study. https://doi.org/10.1103/physreve.82.011305

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