质点积分EFGM法在任意形状模具的塑性成形模拟中的应用  

Application of Element Free Galerkin Method Based on Particle Integration to Plastic Forming of Arbitrarily-shaped Die

作　　者：苏建民[1] 王耘[1] 

机构地区：[1]浙江大学机械与能源工程学院,杭州310027

出　　处：《机械科学与技术》2010年第8期986-991,共6页Mechanical Science and Technology for Aerospace Engineering

摘　　要：对任意形状模具型腔工况下的塑性大变形过程进行高效率的有效数值模拟有实际的工程指导意义,为此笔者将基于质点积分的无网格伽辽金法应用于该过程的分析。质点积分简化了无网格分析中最为耗时的积分运算,可在保证精度的前提下实现高效计算。文中使用有限元网格法描述模具型腔,处理接触界面时,用主从面法进行接触搜索,由罚函数法将接触约束引入变形控制方程,采用显式技术求解系统控制方程。使用上述方法分析带有球头凸模的反挤压铜块工件工艺过程,将计算结果与基于ANSYS/LS-DYNA环境的有限元法得到的结果进行比较,说明了笔者提出方法的正确性和可行性。An elment-free galerkin method（ EFGM） based on particle integration is employed to simulate the large deformation process of a plastic workpiece with arbitrarily-shaped die. The particle integration method simplifies the integration operation which is the most time-consuming process in EFGM,resulting in effective results and highly efficient simulaton speed. The surface of the die cavity in arbitrary shape is represented by triangular finite elements. Regarding the contact surface between the workpiece and the die,a so-called master-slave surface method is used to find out the couples of the nodes on the workpiece and the finite elements on the die surface which might contact each other. We introduce the contact constraints into deformation equation using penalty function method,and solve the equation using the dynamic explicit method based on central difference format. The extrusion process of a copper block under ball-shaped convex mold was simulated as a example,and the results were compared with those obtained by finite element method using ANSYS/LS-DYNA,to prove the correctness and feasibility of our algorithm.

关 键 词：无网格法 质点积分 任意形状模具 显式算法 罚函数法 主从法 

分 类 号：TG3[金属学及工艺—金属压力加工]