Investigation Of Elastic-plastic Rolling Contact Models Of Particle

As an important part of discrete element method,rolling contact model plays an im portant role in predicting the motion state of particle system,understanding the mechanic al details of particles and macroscopic behavior characteristics.In previous studies,many rolling contact models have been proposed.Among them,the elastoplastic spring-dampe r rolling contact model based on physical assumptions is closed to the actual rolling cont act process and is most widely used.The elastic-plastic-spring damping rolling contact model can solve the problem of numerical instability of other models,however,because its simulation parameters are derived from the spring-damp hypothesis,the range and ph ysical meaning of simulation parameters are not clear enough,especially the relationship between simulation parameters and properties of granular materials needs to be suppleme nted urgently.Based on elastic-plastic contact mechanics analysis and finite element analysis,the el astic-plastic rolling contact process of spherical particles is analyzed in dimensionless met hod in this paper.The relationship between rolling resistance of spherical particles in ela stic-plastic rolling process and particle attributes and external loads is obtained.The rolli ng coefficient in elastic-plastic rolling contact model and the physical meaning and variat ion rules of rolling stiffness are also obtained.The elastic-plastic-spring damped rolling c ontact model based on physical assumption is optimized by the corresponding fitting for mula.The results show that in the elastic-plastic contact stage,when the dimensionless p arameters describing the degree of plastic deformation are the same,the dimensionless an gle of particle rolling is the same,and the dimensionless contact pressure distribution on the particle contact surface is the same.Finally,the characteristics and advantages of th e elastic-plastic rolling contact model are illustrated by numerical simulation of single par ticle rolling process and particle accumulation process.