改进的板料成形模拟等效拉深筋约束阻力处理  

Improved numerical constraint disposal method using equivalent drawbead resistance force in sheet metal forming

作　　者：杜亭[1] 谢绍辉[1] 章志兵[1] 柳玉起[1] 

机构地区：[1]华中科技大学材料成形与模具技术国家重点实验室,湖北武汉430074

出　　处：《华中科技大学学报（自然科学版）》2009年第9期94-96,共3页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(50905066);中央高校基本科研业务费专项基金资助项目

摘　　要：基于有限元动力显式增量算法,提出一种新的拉深筋约束阻力处理方法.通过采用线性弹簧单元,将作用在坯料节点上的拉深筋阻力等效为一定刚度的弹簧,通过控制弹簧系数来模拟拉深筋阻力的大小和变换,可以精确地反映板料成形过程中约束阻力被动、同步产生的效果,提高计算精度.将提出的处理方法引入到自主开发的动力显式求解器(称为DEMS),计算了Numisheet 2005行李箱内板的成形过程,计算得出的厚度分布与实验数据符合较好,验证了算法的有效性.The resistance force generated by drawbead geometry are always considered as active force and directly added to the right side of the equations in sheet metal forming simulation, which actually are not in accord with realistic effect. A numerical constraint disposal method was proposed using the linear spring element to represent the passive and synchronous effect of drawbead resistance force to get the higher simulation precision, in which the drawbead restraining force assigned to each node was considered as a linear spring and controlled with the variation of spring rate. The improved numerical constraint disposal method was introduced into the solver named after dynamic explicit method solver （DEMS）, which was based on finite element dynamic explicit method. Drawing process of an automobile decklid panel, the first benchmark of Numisheet 2005, was simulated. The prediction of thickness distribution is shown to be in very good agreement with experimental result, and the method is proved to be effective.

关 键 词：动力显式 等效拉深筋 约束阻力 线性弹簧单元 线性约束处理 

分 类 号：TG386[金属学及工艺—金属压力加工]