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Archimedes' law explains penetration of solids into granular media.

ABSTRACT: Understanding the response of granular matter to intrusion of solid objects is key to modelling many aspects of behaviour of granular matter, including plastic flow. Here we report a general model for such a quasistatic process. Using a range of experiments, we first show that the relation between the penetration depth and the force resisting it, transiently nonlinear and then linear, is scalable to a universal form. We show that the gradient of the steady-state part, K ? , depends only on the medium's internal friction angle, ?, and that it is nonlinear in ??=?tan ?, in contrast to an existing conjecture. We further show that the intrusion of any convex solid shape satisfies a modified Archimedes' law and use this to: relate the zero-depth intercept of the linear part to K ? and the intruder's cross-section; explain the curve's nonlinear part in terms of the stagnant zone's development.

SUBMITTER: Kang W

PROVIDER: S-EPMC5856792 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Archimedes' law explains penetration of solids into granular media.

Kang Wenting W Feng Yajie Y Liu Caishan C Blumenfeld Raphael R

Nature communications 20180316 1

Understanding the response of granular matter to intrusion of solid objects is key to modelling many aspects of behaviour of granular matter, including plastic flow. Here we report a general model for such a quasistatic process. Using a range of experiments, we first show that the relation between the penetration depth and the force resisting it, transiently nonlinear and then linear, is scalable to a universal form. We show that the gradient of the steady-state part, K <sub>ϕ</sub> , depends on ...[more]

PMID: 29549250

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