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arXiv · 2107.12584

Darcy-Reynolds forces during intrusion into granular-fluid beds

Joshua Strader·Neil Causley·Joshua A. Dijksman·Abram H. Clark
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Abstract

We experimentally study intrusion into fluid-saturated granular beds by a free-falling sphere, varying particle size and fluid viscosity. We test our results against Darcy-Reynolds theory, where the deceleration of the sphere is controlled by Reynolds dilatancy and the Darcy flow resistance. We find the observed intruder dynamics are consistent with Darcy-Reynolds theory for varied particle size. We also find that our experimental results for varied viscosity are consistent with Darcy-Reynolds theory, but only for a limited range of the viscosity. For large viscosities, observed forces begin to decrease with increasing viscosity, in contrast with the theoretical prediction.

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Joshua Strader, Neil Causley, Joshua A. Dijksman, Abram H. Clark. 2021-07-27. Darcy-Reynolds forces during intrusion into granular-fluid beds. https://arxiv.org/abs/2107.12584

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