圆盘颗粒DDA接触算法及冲量法  

Contact Algorithm of Disk-Based Particle DDA and Impulse-Based Method

作　　者：陈孚[1] 喻勇[2] 

机构地区：[1]西南交通大学力学与工程学院,成都610031 [2]西南交通大学应用力学与结构安全四川省重点实验室,成都610031

出　　处：《重庆理工大学学报（自然科学）》2016年第11期71-77,共7页Journal of Chongqing University of Technology：Natural Science

基　　金：长江科学院开放研究基金资助项目(CKWV2014206/KY)

摘　　要：介绍了圆盘颗粒不连续变形分析(DDA)理论。推导了圆盘与边界、圆盘与圆盘的罚函数法接触子矩阵。在罚函数法和曾广拉格朗日法下编写程序模拟了单个圆盘与边界碰撞、折斜面上的运动和多圆盘在封闭边界内的运动等3个算例。研究了罚函数法和增广拉格朗日法处理接触时刚度变化对系统机械能的影响,发现碰撞速度较大时,系统机械能的变化在不同刚度取值组合下相差很大。为解决模拟碰撞时存在的机械能变化不准确的问题,在计算中引入冲量法,用于计算圆盘与圆盘、圆盘与边界以及圆盘与凸角碰撞后的分离速度,以更新DDA算法中的初始速度。将冲量法编入程序在不同恢复系数和摩擦角条件下重新模拟算例,发现改善后的算例程序可较好地模拟多圆盘在运动过程中的机械能变化。The theory of disk-based DDA（ Discontinuous Deformation Analysis） is presented. Based on penalty method,the sub-matrices for disk to boundary and disk to disk are derivated. They are as follows： a single disk running into boundaries,a single disk on on multiple slopes and disks within a closed boundary. The influence of penalty value on mechanical energy was studied when penalty method and augmented Lagrangian method are used to deal with the contact. The change of mechanical energy within the system show strong dependence on the stiffness of the system in collisions. To solve the problem above,the impulse-based method is used to calculate the velocityafter every collision. This method is coded into the program of previous examples and simulates movements under different combinations of recovery efficient and friction angle. It is shown that the method can well simulate the mechanical energy of disks within a closed boundary.

关 键 词：圆盘颗粒DDA 接触刚度 机械能 冲量法 

分 类 号：O324[理学—一般力学与力学基础]