Stochastic discrete element modelling of rough particles-a random normal interaction law
Received:May 15, 2016  Revised:June 15, 2016
View Full Text  View/Add Comment  Download reader
DOI:10.7511/jslx201604032
KeyWord:surface roughness  contact law  discrete element method  stochastic DEM  numerical model
           
AuthorInstitution
冯云田 斯旺西大学 辛克维奇计算工程中心, 英国斯旺西SA2 8PP
赵婷婷 斯旺西大学 辛克维奇计算工程中心, 英国斯旺西SA2 8PP
加藤淳 斯旺西大学 辛克维奇计算工程中心, 英国斯旺西SA2 8PP
周伟 武汉大学 水利水电学院, 武汉
Hits: 2417
Download times: 1413
Abstract:
      Particles are assumed smooth in classical discrete element modelling,but real particles have random rough surfaces which may influence their mechanical properties.It is necessary therefore to quantitatively improve the conventional discrete element model particles by taking their surface roughness into consideration.In this work,a new random normal contact law is established for particles that have random rough surfaces.The contact law,based on the classic Greenwood and Williamson (GW) model,is derived by both theoretical derivation and numerical simulation.A Newton-Raphson based numerical solution procedure is proposed to obtain the total contact force for a given overlap and a set of rough surface parameters.Some related computational issues key to improve computational efficiency and accuracy are addressed.Instead of a complicated integral expression involved in the GW model,the curve fitted empirical formula of the random contact law retains the closed form and simplicity of the Hertz model,with only one added parameter, σ, the standard deviation of the surface roughness,and therefore can be readily incorporated into the current discrete element modelling framework.