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arXiv · 1310.0753

Energy decay in three-dimensional freely cooling granular gas

Sudhir N. Pathak·Zahera Jabeen·Dibyendu Das·R. Rajesh
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Abstract

The kinetic energy of a freely cooling granular gas decreases as a power law $t^{-θ}$ at large times $t$. Two theoretical conjectures exist for the exponent $θ$. One based on ballistic aggregation of compact spherical aggregates predicts $θ= 2d/(d+2)$ in $d$ dimensions. The other based on Burgers equation describing anisotropic, extended clusters predicts $θ=d/2$ when $2\le d \le 4$. We do extensive simulations in three dimensions to find that while $θ$ is as predicted by ballistic aggregation, the cluster statistics and velocity distribution differ from it. Thus, the freely cooling granular gas fits to neither the ballistic aggregation or a Burgers equation description.

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Sudhir N. Pathak, Zahera Jabeen, Dibyendu Das, R. Rajesh. 2013-10-02. Energy decay in three-dimensional freely cooling granular gas. https://doi.org/10.1103/physrevlett.112.038001

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