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arXiv · 1710.04452

Rheology of inelastic hard spheres at finite density and shear rate

W. Till Kranz·Fabian Frahsa·Annette Zippelius·Matthias Fuchs·Matthias Sperl
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Abstract

Considering a granular fluid of inelastic smooth hard spheres we discuss the conditions delineating the rheological regimes comprising Newtonian, Bagnoldian, shear thinning, and shear thickening behavior. Developing a kinetic theory, valid at finite shear rates and densities around the glass transition density, we predict the viscosity and Bagnold coefficient at practically relevant values of the control parameters. The determination of full flow curves relating the shear stress $σ$ to the shear rate $\dotγ$, and predictions of the yield stress complete our discussion of granular rheology derived from first principles.

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W. Till Kranz, Fabian Frahsa, Annette Zippelius, Matthias Fuchs, Matthias Sperl. 2018-07-11. Rheology of inelastic hard spheres at finite density and shear rate. https://doi.org/10.1103/physrevlett.121.148002

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