Investigation of local process in granular segregation based on discrete element method

The phenomenon of granular size segregation under vibration has plagued researchers due to the unsteady and high particle number concentration. Discrete element method (DEM) is employed to simulate the process of intruder rising through small background particles from the bottom to the top in a cylindrical container. To describe the segregation level during this process, a segregation evaluation parameter, alpha, is introduced. It is found that the granular process can be divided into two stages according to the evaluation of alpha, an initial stage (IS) and a stable intermediate stage (SIS). For a better understanding of the segregation process in these different stages, a new viewpoint focused on the local processes is presented in this article. The segregation mechanism is clarified through numerical simulation of local processes and reference to previous research results. (c) 2022 The Society of Powder Technology Japan. Published by Elsevier BV and The Society of Powder Technology Japan. All rights reserved.