화학공학소재연구정보센터
Powder Technology, Vol.312, 194-203, 2017
Discrete element modelling study of force distribution in a 3D pile of spherical particles
We present a numerical analysis of the transmission of contact forces in a granular pile comprising 50,000 frictional, coarse spherical particles. The goal of our study is to understand the microscopic origins of macroscopic behaviours, such as the pressure dip at the centre of the base of a conical pile. The particles are 8.2 mm in diameter with a standard deviation of 0.1 mm to avoid ordering effects. The effects of the pouring method, inter-particle sliding friction and rolling friction on the distribution of static stress are examined. The analysed microscopic variables are the distributions of the values and directions of the contact forces as well as the degree of mobilisation of contact friction. The vertical, radial and shear stress components are derived from the discrete contact forces. The analysed macroscopic variables are the distribution of the stress components, mobilisation of internal friction and inclination of the major principal stress to the vertical. The simulation results show that certain combinations of the examined factors lead to the formation of dome-shaped structures of maximum values of mean pressure as determined by the stress distribution inside the pile as well as at its base. (C) 2017 Elsevier B.V. All rights reserved.