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Logarithmic density relaxation in compaction of granular materials

Gongwen Peng·Takao Ohta
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Abstract

On the basis of physical considerations we propose a one-dimensional discrete lattice model for the density relaxation of granular materials under tapping. Solving the difference equation numerically, we find a logarithmic time-dependence of the density relaxation. This is in agreement with experimental results of Knight et al. [Phys. Rev. E 51, 3957(1995)]. The origin of this anomalous relaxation is elucidated analytically by solving the equation of its continuum version asymptotically in time.

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Gongwen Peng, Takao Ohta. 1997-07-23. Logarithmic density relaxation in compaction of granular materials. https://doi.org/10.1103/physreve.57.829

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