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arXiv · 0809.4432

Long-time tails and cage effect in driven granular fluids

Andrea Fiege·Timo Aspelmeier·Annette Zippelius
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Abstract

We study the velocity autocorrelation function (VACF) of a driven granular fluid in the stationary state in 3 dimensions. As the critical volume fraction of the glass transition in the corresponding elastic system is approached, we observe pronounced cage effects in the VACF as well as a strong decrease of the diffusion constant. At moderate densities the VACF is shown to decay algebraically in time (t^{-3/2}) like in a molecular fluid, as long as the driving conserves momentum locally.

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Andrea Fiege, Timo Aspelmeier, Annette Zippelius. 2008-09-25. Long-time tails and cage effect in driven granular fluids. https://doi.org/10.1103/physrevlett.102.098001

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