基于多项式混沌展开的冲压不确定性分析

Uncertainty analysis of stamping based on polynomial chaotic expansions

为分析冲压过程的不确定性,提出基于多项式混沌展开的分析方法,首先根据生产现场实际情况,确定冲压工艺设计变量的概率分布类型,并计算对应的一维正交多项式基底;然后利用PCE展开原则,生成冲压成形评价指标的多维正交多项式,在此基础上计算评价指标的统计矩,评估设计变量对评价指标波动的贡献率;最后运用蒙特卡洛法拟合生成评价指标的累积分布函数,获得更详细的冲压过程不确定性定量评估结果,并以端盖零件为例进行冲压不确定性分析。结果表明:该方法合理、有效,能够准确评估冲压过程的不确定性。

In order to analyze the uncertainty of stamping process,an analytical method based on polynomial chaotic expansion was proposed.Firstly,according to the actual situation of produc⁃tion site,the probability distribution types of design variables of stamping process were deter⁃mined,and the corresponding one-dimensional orthogonal polynomial basis was calculated.Then,based on the principle of PCE expansion,the multi-dimensional orthogonal polynomial of the eval⁃uation index of stamping forming was generated.On this basis,the statistical moment of the evalu⁃ation index was calculated and the contribution rate of the design variable to the fluctuation of the evaluation index was evaluated.Finally,Monte Carlo method was used to fit the cumulative distri⁃bution function of the evaluation index,and then more detailed quantitative evaluation results of stamping process uncertainty were obtained.Taking the stamping uncertainty analysis of the end cover part as an example,the results showed that the method was reasonable,effective,and could accurately evaluate the stamping process uncertainty.