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Measurements of Grain Motion in a Dense, Three-Dimensional Granular Fluid

Xiaoyu Yang·Chao Huan·D. Candela·R. W. Mair·R. L. Walsworth
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Abstract

We have used an NMR technique to measure the short-time, three-dimensional displacement of grains in a system of mustard seeds vibrated vertically at 15g. The technique averages over a time interval in which the grains move ballistically, giving a direct measurement of the granular temperature profile. The dense, lower portion of the sample is well described by a recent hydrodynamic theory for inelastic hard spheres. Near the free upper surface the mean free path is longer than the particle diameter and the hydrodynamic description fails.

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Xiaoyu Yang, Chao Huan, D. Candela, R. W. Mair, R. L. Walsworth. 2001-11-29. Measurements of Grain Motion in a Dense, Three-Dimensional Granular Fluid. https://doi.org/10.1103/physrevlett.88.044301

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