薄板起皱失稳数值模拟计算方法

Numerical Simulation Methods of Sheet Metal Wrinkling Instability Problem

汽车、航天、航空等领域的零件制造轻量化趋势致使管板材成形起皱失稳缺陷的预测成为行业的重点关注问题。基于目前常规数值模拟算法未包含起皱失稳判据从而无法解决起皱数值预测的现状,利用平板对角拉伸试验作为对比验证对象,利用大型平台软件ABAQUS证实了用于模拟薄板变形的常规壳单元动态显式算法(*DYNAMIC)以及用于结构件屈曲计算的弧长法(*RIKS)无法用于计算薄板成形起皱问题,尝试并比较了"用于微缺陷引入的特征值分析(*BUCKLE)+*DYNAMIC分析"相结合分析方法、"*BUCKLE分析+*RIKS分析"相结合的分析方法以及"三维实体单元动态显式算法"三种方式对薄板起皱失稳问题的运算结果,围绕计算精度、适用范围、算法特征等方面对这三种算法进行研究,确立了从多方面考察综合性能最佳的薄板成形起皱失稳数值模拟方法。

The light weight of parts manufacturing in the automotive, aerospace and aerospace industries has led to the prediction of wrinkling instability defects in sheet metal forming, which has become a major concern of the industry. However, based on the current status of conventional numerical simulation algorithms that do not include wrinkle instability criteria and thereout cannot implement the wrinkle numerical predictions, the plate diagonal tensile testing is used as a comparative verification object to find the proper numerical prediction methods for wrinkling instability. With the platform software ABAQUS it is confirmed that the conventional shell element dynamic algorithm(*DYNAMIC) used to simulate the deformation of thin-walled parts and the arc length method(*RIKS) used for structural part buckling calculation cannot be used to calculate the wrinkle problem of sheet metal forming. Three ways of sheet wrinkling instability prediction method: 'the eigenvalue analysis(* BUCKLE analysis) for microdefects introduction + *DYNAMIC analysis', '*BUCKLE analysis + *RIKS analysis' and 'three-dimensional solid element dynamic display algorithm' are tried and compared with the tests. The three algorithms are studied in terms of calculation accuracy, application scope, and algorithm features. The numerical simulation method with the best comprehensive performance for solving the wrinkling instability problem in sheet metal forming is established.