Diffusion and mobility in a stirred dense granular material.

Junfei Geng; R P Behringer

doi:10.1103/physrevlett.93.238002

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Diffusion and mobility in a stirred dense granular material.

Junfei Geng·R P Behringer

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Abstract

We describe a probe of diffusivity (D) and mobility (B) for a dense 2D granular system. We introduce random motion by stirring, and characterize D by particle tracking. To measure B we measure the force needed to push a particle through the medium at fixed velocity, v, using three sizes of tracer particle. We find simple Brownian diffusion, but B depends strongly on v because the force needed to push a tracer through a sample is nearly independent of v. Data for D/B depend on the tracer particle size.

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Biophysical Phenomena Biophysics Diffusion Motion Movement Physics Stress, Mechanical Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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Junfei Geng, R P Behringer. 2004-12-02. Diffusion and mobility in a stirred dense granular material.. https://doi.org/10.1103/physrevlett.93.238002

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