伴随多面体粒子破碎的散粒体系统离散元数值研究

项目名称： 伴随多面体粒子破碎的散粒体系统离散元数值研究

项目编号： No.11302049

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 洪俊

作者单位： 东南大学

项目金额： 23万元

中文摘要： 发射药床在外载荷作用下的部分药粒发生破碎问题，其实质是伴随部分粒子脆性破碎的多面体粒子组成的散粒体系统力学问题。针对发射药床初始堆积结构仅需药粒位置和方位特点，解决空间接触识别算法难题，合理选择接触模型，优化多面体粒子组成的散粒体系统离散元程序，生成密实的发射药床初始堆积结构；针对发射药粒破碎定量研究特点，合理选择脆性材料的破碎模型，结合复变量求导法及试验解决破碎模型中计算参数选取难题，采用基于离散元的弹簧-球单元随机破碎模型数值研究发射药粒不同工况下的破碎问题；有机结合破碎模型和多面体单元散粒体系统离散元程序，部分解决接触参数完全试算问题，通过整合和进一步发展现有的离散单元法，研发能够解决伴随部分粒子破碎的多面体粒子组成的散粒体系统受力分析的数值方法和程序，数值研究发射药床的力学性能。为解决发射药床伴随脆性药粒破碎的散粒体系统力学问题提供技术保障，为高性能火炮研制提供科学依据。

中文关键词： 散粒体系统；离散元；多面体；破碎；数值研究

英文摘要： The problem that the partial particles in propellant bed are fracture under the load is the mechanical problem of granular system with partial polyhedral particles' brittle fracture. Dense accumulated structure of granular system which is made up of many polyhedral particles only need the position and angle of the particles. The code of discrete element method which describes granular system made up of the polyhedral particles is optimized. The optimized ways are to use the fast contact detection algorithm and reasonable contact model. Especially, the fast contact detection algorithm is the key technique. And then, the dense accumulated structure of propellant bed is obtained through using the code. In order to study the brittle fracture level of single particle, the spring-sphere random fracture model based on discrete element method is reasonably chosen. The anther key technique, associating the complex variable differentiation and experiment, is used to solve the problem of computational parameters. And then, propellant particles are numerical simulated under the different conditions. Combined application between the brittle fracture model and the code of discrete element method which describes granular system made up of the polyhedral particles, and partially solving the problem that the contact parameters a

英文关键词： granular system；discrete element method；polyhedral particles；fracture；Numerical study