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Close-packed floating clusters: granular hydrodynamics beyond the freezing point?

Baruch Meerson·Thorsten Poeschel·Yaron Bromberg
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Abstract

Monodisperse granular flows often develop regions with hexagonal close packing of particles. We investigate this effect in a system of inelastic hard spheres driven from below by a "thermal" plate. Molecular dynamics simulations show, in a wide range of parameters, a close-packed cluster supported by a low-density region. Surprisingly, the steady-state density profile, including the close-packed cluster part, is well described by a variant of Navier-Stokes granular hydrodynamics (NSGH). We suggest a simple explanation for the success of NSGH beyond the freezing point.

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Baruch Meerson, Thorsten Poeschel, Yaron Bromberg. 2003-05-28. Close-packed floating clusters: granular hydrodynamics beyond the freezing point?. https://doi.org/10.1103/physrevlett.91.024301

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