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Elastic Energy, Fluctuations and Temperature for Granular Materials

Lou Kondic·R. P. Behringer
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Abstract

We probe, using a model system, elastic and kinetic energies for sheared granular materials. For large enough $P/E_y$ (pressure/Young's modulus) and $P/ρv^2$ ($P/$kinetic energy density) elastic dominates kinetic energy, and energy fluctuations become primarily elastic in nature. This regime has likely been reached in recent experiments. We consider a generalization of the granular temperature, $T_g$, with both kinetic and elastic terms and that changes smoothly from one regime to the other. This $T_g$ is roughly consistent with a temperature adapted from equilibrium statistical mechanics.

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Lou Kondic, R. P. Behringer. 2003-07-23. Elastic Energy, Fluctuations and Temperature for Granular Materials. https://doi.org/10.1209/epl%2Fi2004-10061-5

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