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arXiv · 0704.1806

Critical Scaling of Shear Viscosity at the Jamming Transition

Peter Olsson·S. Teitel
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Abstract

We carry out numerical simulations to study transport behavior about the jamming transition of a model granular material in two dimensions at zero temperature. Shear viscosity ηis computed as a function of particle volume density ρand applied shear stress σ, for diffusively moving particles with a soft core interaction. We find an excellent scaling collapse of our data as a function of the scaling variable σ/|ρ_c-ρ|^Δ, where ρ_c is the critical density at σ=0 ("point J"), and Δis the crossover scaling critical exponent. Our results show that jamming is a true critical phenomenon, extending to driven steady states along the non-equilibrium σaxis of the ρ-σphase diagram.

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Peter Olsson, S. Teitel. 2007-10-26. Critical Scaling of Shear Viscosity at the Jamming Transition. https://doi.org/10.1103/physrevlett.99.178001

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