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arXiv · 1806.01574

Hydrodynamics of granular particles on a line

A. Baldassarri·A. Puglisi·A. Prados
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Abstract

We investigate a lattice model representing a granular gas in a thin channel. We deduce the hydrodynamic description for the model from the microscopic dynamics in the large system limit, including the lowest finite-size corrections. The main prediction from hydrodynamics, when finite-size corrections are neglected, is the existence of a steady "uniform longitudinal flow" (ULF), with the granular temperature and the velocity gradient both uniform and directly related. Extensive numerical simulations of the system show that such a state can be observed in the bulk of a finite-size system by attaching two thermostats with the same temperature at its boundaries. The relation between the ULF state and the shocks appearing in the late stage of a cooling gas of inelastic hard rods is discussed.

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A. Baldassarri, A. Puglisi, A. Prados. 2018-06-05. Hydrodynamics of granular particles on a line. https://doi.org/10.1103/physreve.97.062905

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