基于超二次曲面的非球形离散单元模型研究

Study of discrete element model for non-sphere particles base on super-quadrics

通过对颗粒体系接触过程的运动学和动力学分析,建立了一种基于超二次曲面的非球形离散单元模型,该模型避免了球形接触模型描述颗粒形状的局限性,使离散单元法更接近物理事实,并在此基础上提出了计算求解模型的数值方法,实现了对复杂形状的颗粒体系的模拟计算。将所建立的数值计算方法进行了编程实现,并对模型和算法进行了算例测试,证实了本文所建立的非球形离散单元模型的可行性和正确性。测试结果表明,本文的模型能够比较准确地模拟复杂颗粒体系的真实运动,可为复杂颗粒体系的模拟研究提供一种新的数值计算方法。

A dry contact model of discrete element method has been established which is based on superquadrics by the kinematics and dynamics analysis from the contact process of dry particle system.The model made the mathematic description of the relationship of force and deformation between particles closer to the reality of the movement of particle system.The limitation coming from using spherical-contact model has been avoided to describe the contact of particles so that it made the contacting discrete element model closer to physical reality and a numerical method has been proposed to calculate the model to achieve the simulation of dry particle system with complex particle shape.A program is developed which contains the proposed contacting discrete element model.The feasibility and correctness of the model established in the paper had been proved by testing the validity of the model and the algorithms.As a new numerical calculation method to study particle system,the model described in the paper can simulate the real motion of complex particle system accurately.