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DSMC evaluation of the Navier-Stokes shear viscosity of a granular fluid

J. M. Montanero·A. Santos·V. Garzo
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Abstract

A method based on the simple shear flow modified by the introduction of a deterministic non-conservative force and a stochastic process is proposed to measure the Navier-Stokes shear viscosity in a granular fluid described by the Enskog equation. The method is implemented in DSMC simulations for a wide range of values of dissipation and density. It is observed that, after a certain transient period, the system reaches a hydrodynamic stage which tends to the Navier-Stokes regime for long times. The results are compared with theoretical predictions obtained from the Chapman-Enskog method in the leading Sonine approximation, showing quite a good agreement, even for strong dissipation.

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BibTeXRIS

J. M. Montanero, A. Santos, V. Garzo. 2004-11-09. DSMC evaluation of the Navier-Stokes shear viscosity of a granular fluid. https://doi.org/10.1063/1.1941632

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