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Towards a continuum theory of clustering in a freely cooling inelastic gas

Baruch Meerson·Andrea Puglisi
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Abstract

We performed molecular dynamics simulations to investigate the clustering instability of a freely cooling dilute gas of inelastically colliding disks in a quasi-one-dimensional setting. We observe that, as the gas cools, the shear stress becomes negligibly small, and the gas flows by inertia only. Finite-time singularities, intrinsic in such a flow, are arrested only when close-packed clusters are formed. We observe that the late-time dynamics of this system are describable by the Burgers equation with vanishing viscosity, and predict the long-time coarsening behavior.

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Baruch Meerson, Andrea Puglisi. 2005-03-31. Towards a continuum theory of clustering in a freely cooling inelastic gas. https://doi.org/10.1209/epl%2Fi2004-10507-8

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