Particle dynamics in sheared granular matter

W. Losert; L. Bocquet; T. C. Lubensky; J. P. Gollub

doi:10.1103/physrevlett.85.1428

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Particle dynamics in sheared granular matter

W. Losert·L. Bocquet·T. C. Lubensky·J. P. Gollub

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Abstract

The particle dynamics and shear forces of granular matter in a Couette geometry are determined experimentally. The normalized tangential velocity $V(y)$ declines strongly with distance $y$ from the moving wall, independent of the shear rate and of the shear dynamics. Local RMS velocity fluctuations $δV(y)$ scale with the local velocity gradient to the power $0.4 \pm 0.05$. These results agree with a locally Newtonian, continuum model, where the granular medium is assumed to behave as a liquid with a local temperature $δV(y)^2$ and density dependent viscosity.

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BibTeX RIS

W. Losert, L. Bocquet, T. C. Lubensky, J. P. Gollub. 2000-04-24. Particle dynamics in sheared granular matter. https://doi.org/10.1103/physrevlett.85.1428

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