Numerical experiments on transverse motion and force chains of solids in rotating cylinders

被引：2

作者：

State Key Laboratory of High Performance Complex Manufacturing, School of Mechanical and Electrical Engineering, Central South University, Changsha ^{[1
]}

410083, China

不详 ^{[2
]}

410075, China

机构：

[1] State Key Laboratory of High Performance Complex Manufacturing, School of Mechanical and Electrical Engineering, Central South University, Changsha

[2] School of Traffic and Transportation Engineering, Central South University, Changsha

来源：

Zhongnan Daxue Xuebao (Ziran Kexue Ban) | / 7卷 / 2446-2451期

基金：

中国博士后科学基金; 中国国家自然科学基金;

关键词：

Discrete element method; Force chains; Rotating cylinders; Transverse bed motion;

D O I：

10.11817/j.issn.1672-7207.2015.07.009

中图分类号：

学科分类号：

摘要：

Taking account of the interactions between particles, a kinematic model of granular bed in rotating kiln was established using discrete element method based on its particle size. Using spherical quartz sand as bed material, transverse bed motions and particle force chains were studied through numerical calculation of the model. Taking the Froude number, filling angle, and wall friction coefficient as variables, six forms of transverse bed motion observed in experimental tests were simulated: sliding, slumping, rolling, cascading, cataracting and centrifuging. The results show that the force chains within the bed consist of two parts: the surface area with weak chain (about 10% of the bed thickness) and the underlying area with strong chain. In case of sliding, slumping, rolling and cascading, the force chains of the underlying area are stable and the particles are relatively static. However, the force chains of the surface area are broken and restructured frequently, which makes the material particles move downward and mix together. The specific motion is determined by rotate speed and force chain breaking-restructuring speed. Contracts between bed particles in the form of cascading are the most savage for actual operation. ©, 2015, Central South University of Technology. All right reserved.

引用

页码：2446 / 2451

页数：5

共 15 条

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