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arXiv · 1910.07073

Intruder in a two-dimensional granular system: Effects of dynamic and static basal friction on stick-slip and clogging dynamics

C. Manuel Carlevaro·Ryan Kozlowski·Luis A. Pugnaloni·Hu Zheng·Joshua E. S. Socolar·Lou Kondic
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Abstract

We discuss the results of simulations of an intruder pulled through a two-dimensional granular system by a spring, using a model designed to lend insight into the experimental findings described by Kozlowski et al. [Phys. Rev. E, 100, 032905 (2019)]. In that previous study the presence of basal friction between the grains and the base was observed to change the intruder dynamics from clogging to stick-slip. Here we first show that our simulation results are in excellent agreement with the experimental data for a variety of experimentally accessible friction coefficients governing interactions of particles with each other and with boundaries. Then, we use simulations to explore a broader range of parameter space, focusing on the friction between the particles and the base. We consider a range of both static and dynamic basal friction coefficients, which are difficult to vary smoothly in experiments. The simulations show that dynamic friction strongly affects the stick-slip behaviour when the coefficient is decreased below 0.1, while static friction plays only a marginal role in the intruder dynamics.

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C. Manuel Carlevaro, Ryan Kozlowski, Luis A. Pugnaloni, Hu Zheng, Joshua E. S. Socolar, Lou Kondic. 2019-10-15. Intruder in a two-dimensional granular system: Effects of dynamic and static basal friction on stick-slip and clogging dynamics. https://doi.org/10.1103/physreve.101.012909

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