Percolation of a fine particle in static granular beds
Percolation of a fine particle in static granular beds
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细颗粒在静态颗粒床中的渗透
DOI：
10.1103/physreve.107.014903
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发表时间：
2023
影响因子：
2.4
通讯作者：
Lueptow, Richard M.
中科院分区：
文献类型：
--
作者：
Gao, Song;Ottino, Julio M.;Umbanhowar, Paul B.;Lueptow, Richard M.
本文采用离散元方法模拟研究了重力作用下球形细颗粒在静态随机堆积大颗粒床中的渗流行为。在几何捕集阈值处的颗粒尺寸比由三个接触的大颗粒定义，将渗流行为分为通过和捕集状态。然而，平均渗流速度和扩散的未捕获的细颗粒，这取决于both，是类似的，在这两个制度，并可以崩溃的范围和适当的缩放。得到了基于局部孔喉的局部渗流速度与细颗粒粒径比和堆积密度的经验关系式，该关系式适用于我们所研究的整个粒径比和堆积密度范围。类似地，在捕获机制中，细颗粒到达给定深度的概率由简单的统计模型很好地描述。最后，渗流速度和细颗粒扩散被发现随恢复系数的增加而减小。
We study the percolation of a fine spherical particle under gravity in static randomly packed large-particle beds with different packing densitiesand large to fine particle size ratiosranging from 4 to 7.5 using discrete element method simulations. The particle size ratio at the geometrical trapping threshold, defined by three touching large particles,, divides percolation behavior into passing and trapping regimes. However, the mean percolation velocity and diffusion of untrapped fine particles, which depend on bothand, are similar in both regimes and can be collapsed over a range ofandwith the appropriate scaling. An empirical relationship for the local percolation velocity based on the local pore throat to fine particle size ratio and packing density is obtained, which is valid for the full range of size ratio and packing density we study. Similarly, in the trapping regime, the probability for a fine particle to reach a given depth is well described by a simple statistical model. Finally, the percolation velocity and fine particle diffusion are found to decrease with increasing restitution coefficient.