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arXiv · cond-mat/0605634

Thermal collapse of a granular gas under gravity

Dmitri Volfson·Baruch Meerson·Lev S. Tsimring
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Abstract

Free cooling of a gas of inelastically colliding hard spheres represents a central paradigm of kinetic theory of granular gases. At zero gravity the temperature of a freely cooling homogeneous granular gas follows a power law in time. How does gravity, which brings inhomogeneity, affect the cooling? We combine molecular dynamics simulations, a numerical solution of hydrodynamic equations and an analytic theory to show that a granular gas cooling under gravity undergoes thermal collapse: it cools down to zero temperature and condenses on the bottom of the container in a finite time.

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Dmitri Volfson, Baruch Meerson, Lev S. Tsimring. 2006-05-25. Thermal collapse of a granular gas under gravity. https://doi.org/10.1103/physreve.73.061305

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