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arXiv · 0804.0477

Rheology and dynamical heterogeneity in frictionless beads at jamming density

Takahiro Hatano
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Abstract

We investigate the rheological properties of an assembly of inelastic (but frictionless) particles close to the jamming density using numerical simulation, in which uniform steady states with a constant shear rate $\dotγ$ is realized. The system behaves as a power-law fluid and the relevant exponents are estimated; e.g., the shear stress is proportional to $\dotγ^{1/δ_S}$, where $1/δ_S=0.64(2)$. It is also found that the relaxation time $τ$ and the correlation length $ξ$ of the velocity increase obeying power laws: $τ\sim\dotγ^{-β}$ and $ξ\sim\dotγ^{-α}$, where $β=0.27(3)$ and $α=0.23(3)$.

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Takahiro Hatano. 2015-12-20. Rheology and dynamical heterogeneity in frictionless beads at jamming density. https://doi.org/10.1088/1742-6596%2F319%2F1%2F012011

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