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arXiv · 2210.01992

Capturing the dynamics of a two orifice silo with the {\mu}(I) model and extensions

Samuel K Irvine·Luke A Fullard·Daniel J Holland·Daniel A Clarke·Thomasin A Lynch·Pierre-Yves Lagrée
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Abstract

Granular material in a silo with two openings can display a `flow rate dip', where a non-monotonic relationship between flow rate and orifice separation occurs. In this paper we study continuum modelling of the silo with two openings. We find that the $\mu(I)$ rheology can capture the flow rate dip if physically relevant friction parameters are used. We also extend the model by accounting for wall friction, dilatancy, and non-local effects. We find that accounting for the wall friction using a Hele-Shaw model better replicates the qualitative characteristics of the flow rate dip seen in experimental data, while dilatancy and non-local effects have very little effect on the qualitative characteristics of the mass flow rate dip. However, we find that all three of these factors have a significant impact on the mass flow rate, indicating that a continuum model which accurately predicts flow rate will need to account for these effects.

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Samuel K Irvine, Luke A Fullard, Daniel J Holland, Daniel A Clarke, Thomasin A Lynch, Pierre-Yves Lagrée. 2022-10-05. Capturing the dynamics of a two orifice silo with the {\mu}(I) model and extensions. https://arxiv.org/abs/2210.01992

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