Fraction of Clogging Configurations Sampled by Granular Hopper Flow
Fraction of Clogging Configurations Sampled by Granular Hopper Flow
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DOI：
10.1103/physrevlett.114.178001
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发表时间：
2015-04-28
影响因子：
8.6
通讯作者：
Durian, D. J.
中科院分区：
文献类型：
--
作者：
Thomas, C. C.;Durian, D. J.
我们根据各种孔径几何形状的堵塞事件之间排出的平均质量，测量堵塞之前流动颗粒构型的分数 F。通过倾斜料斗，我们证明 F 是沿排出颗粒速度方向投影的孔面积的函数。通过改变狭缝的长度，我们证明颗粒堵塞的方式与它们从一组较小的独立圆形开口流出时的方式相同。 F 的折叠数据可以拟合孔宽度指数衰减，该衰减是系统维数的幂。这与一个简单的模型一致，在该模型中，孔附近的单个颗粒在发生堵塞之前有很大但恒定的概率。这样的图意味着不存在急剧的堵塞转变，并且所有料斗都具有非零的堵塞概率。
We measure the fraction F of flowing grain configurations that precede a clog, based on the average mass discharged between clogging events for various aperture geometries. By tilting the hopper, we demonstrate that F is a function of the hole area projected in the direction of the exiting grain velocity. By varying the length of slits, we demonstrate that grains clog in the same manner as if they were flowing out of a set of smaller independent circular openings. The collapsed data for F can be fit to a decay that is exponential in hole width raised to the power of the system dimensionality. This is consistent with a simple model in which individual grains near the hole have a large but constant probability to precede a clog. Such a picture implies that there is no sharp clogging transition, and that all hoppers have a nonzero probability to clog.