关键词: 离散元法, 边界建模, 颗粒材料, 接触检测, 计算机辅助设计/计算机辅助工程

Abstract: To establish the analysis model of boundaries from their three-dimensional Computer Aided Design (CAD) model in the three-dimensional Discrete Element Method (DEM), a novel method for modeling boundaries based on the graphic elements and concepts of real-boundary and virtual-boundary graphic elements were put forward. Based on these, the algorithms for contact detection, the calculation for contact points and the contact overlap of sphere particles and the three-dimensional graphic elements were established, the graphic elements including the surface of circle flat, cone and cylinder, etc., over twenty kinds of the graphic elements were also advanced. By several application examples, correctness and effectiveness of the proposed method were validated. It laid foundations for implementing DEM simulation and analysis of working process of machine parts by their three-dimensional CAD model in design process.

Key words: discrete element method, boundaries modeling, granular materials, contact detection, computer aided design/computer aided engineering