采用局部-整体映射模型的壁板铆接变形预测

Prediction of Riveting Deformation of Aircraft Panel Using Local-Global Mapping Approach

针对现有壁板铆接变形预测方法预测精度低、计算周期长的问题,提出了一种采用局部-整体映射模型的壁板铆接变形预测方法。依据壁板装配工艺流程分析,确定了引起壁板铆接变形的主要原因;结合增扩自由度法,解决了壁板铆接体-壳连接建模中的应力不协调问题,并用于构建壁板铆接局部-整体映射模型;基于局部-整体映射模型,将钉孔周围复杂的应力应变状态传递到壁板整体薄壳模型上,实现了壁板铆接变形预测。计算结果表明:在十钉铆接结构中,与全实体动态铆接模型相比,单钉的平均计算时间从55min降为15min,变形分布与大小基本相同;某壁板变形预测结果与实验结果相比,测量点的最大变形值偏差为0.062mm,平均偏差为0.01mm,相关性系数为0.898。该模型显著提高了计算效率,且具有有效性,为进一步铆接变形的控制研究提供了理论依据。

A novel prediction method of riveting deformation of aircraft panels is proposed to solve the problems of low prediction accuracy and long calculation time in existing prediction methods.Through the analysis on the panel assembly process,the major causes of the panel deformation are identified.Combining with the DOF expanding method,the additional stress arising in the normal connection method is avoided.Then the method is used to establish a local global mapping model.Based on this model,the complex stress strain state around the rivet hole is transferred to the thin shell model of panel in a relatively simple way.Finally,the prediction of riveting deformation of large panel is achieved.The results show that,compared with dynamic explicit finite element model,the average calculation time of a single rivet is decreased from55minutes to15minutes,and the deformation distribution and magnitude of ten rivet structure are basically identical.Comparing the predicted results with experimental results of a aircraft panel,the deviation of maximum deformation values is0062mm,the deviation of average deformation values is001mm,and the correlation coefficient between them is0898.The proposed method improves the computational efficiency and is proved effective.This study may provide a theoretical basis for the control of riveting deformation.