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arXiv · 1711.06119

Clogging in constricted suspension flows

Alvaro Marin·Henri Lhuissier·Massimiliano Rossi·Christian J. Kaehler
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Abstract

The flow of a charged-stabilized suspension through a single constricted channel is studied experimentally by tracking the particles individually. Surprisingly, the behavior is found to be qualitatively similar to that of inertial dry granular systems: For small values of the neck-to-particle size ratio (D/d<3), clogs form randomly as arches of particle span the constriction. The statistics of the clogging events are Poissonian as reported for granular systems and agree, for moderate particle volume fraction ($ϕ\approx20\%$), with a simple stochastic model for the number of particles at the neck. For larger neck sizes (D/d>3), even at the largest $ϕ$ ($\approx60\%$) achievable in the experiments, an uninterrupted particle flow is observed, which resembles that of an hourglass. This particularly small value of D/d at the transition to a practically uninterrupted flow is attributed to the low effective friction between the particles, achieved by the particle's functionalization and lubrication.

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Alvaro Marin, Henri Lhuissier, Massimiliano Rossi, Christian J. Kaehler. 2017-11-16. Clogging in constricted suspension flows. https://doi.org/10.1103/physreve.97.021102

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