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arXiv · 2010.09848

Critical Scaling of Compression-Driven Jamming of Athermal Frictionless Spheres in Suspension

Anton Peshkov·S. Teitel
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Abstract

We study numerically a system of athermal, overdamped, frictionless spheres, as in a non-Brownian suspension, in two and three dimensions. Compressing the system isotropically at a fixed rate $\dot\epsilon$, we investigate the critical behavior at the jamming transition. The finite compression rate introduces a control timescale, which allows one to probe the critical timescale associated with jamming. As was found previously for steady-state shear-driven jamming, we find for compression-driven jamming that pressure obeys a critical scaling relation as a function of packing fraction $\phi$ and compression rate $\dot\epsilon$, and that the bulk viscosity $p/\dot\epsilon$ diverges upon jamming. A scaling analysis determines the critical exponents associated with the compression-driven jamming transition. Our results suggest that stress-isotropic, compression-driven, jamming may be in the same universality class as stress-anisotropic, shear-driven, jamming.

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Anton Peshkov, S. Teitel. 2020-10-19. Critical Scaling of Compression-Driven Jamming of Athermal Frictionless Spheres in Suspension. https://doi.org/10.1103/physreve.103.l040901

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