Three-dimensional clogging structures of granular spheres near hopper orifice  

作　　者：Jing Yang Dianjinfeng Gong Xiaoxue Wang Zhichao Wang Jianqi Li Bingwen Hu Chengjie Xia 杨敬;宫殿锦丰;汪晓雪;王志超;李建奇;胡炳文;夏成杰(Shanghai Key Laboratory of Magnetic Resonance,School of Physics and Electronic Science,East China Normal University,Shanghai 200241,China)

机构地区：[1]Shanghai Key Laboratory of Magnetic Resonance,School of Physics and Electronic Science,East China Normal University,Shanghai 200241,China

出　　处：《Chinese Physics B》2022年第1期388-394,共7页中国物理B（英文版）

基　　金：the China Postdoctoral Science Foundation(Grant Nos.2018M641957 and 2019T120319);the National Natural Science Foundation of China(Grant No.11904102);the Fundamental Research Funds for the Central Universities,China.

摘　　要：The characteristic clogging structures of granular spheres blocking three-dimensional granular flow through hopper outlet are analyzed based on packing structures reconstructed using magnetic resonance imaging techniques.Spheres in clogging structures are arranged in a way with typical features of load-bearing,such as more contacting bonds close to the horizontal plane and more mutually-stabilized contact configurations than packing structures away from the orifice.The requirement of load-bearing inevitably leads to the cooperativity of clogging structures with a correlation length of several particle diameters.This correlation length being comparable with the orifice diameter suggests that a clogging structure is composed of several mutually-stabilized structural motifs to span the orifice perimeter,instead of a collection of independent individual spheres to cover the whole orifice area.Accordingly,we propose a simple geometric model to explain the unexpected linear dependence of the average size of three-dimensional clogging structures on orifice diameter.

关 键 词：granular materials CLOGGING magnetic resonance imaging 

分 类 号：TB30[一般工业技术—材料科学与工程] TP391.41[自动化与计算机技术—计算机应用技术]