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Non-Gaussian Velocity Distribution Function in a Vibrating Granular Bed

Atsushi Kawarada·Hisao Hayakawa
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Abstract

The simulation of granular particles in a quasi two-dimensional container under the vertical vibration as an experimental accessible model for granular gases is performed. The velocity distribution function obeys an exponential-like function during the vibration and deviates from the exponential function in free-cooling states. It is confirmed that this exponential-like distribution function is produced by Coulomb's friction force. A Langevin equation with Coulomb's friction is proposed to describe the motion of such the system.

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Atsushi Kawarada, Hisao Hayakawa. 2004-06-22. Non-Gaussian Velocity Distribution Function in a Vibrating Granular Bed. https://doi.org/10.1143/jpsj.73.2037

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