中文摘要：

基于Ansysls—dyna及Ls—prepost的对同曲率弯管连续二次弯曲进行数值模拟。利用Ansysls—dy—na软件，基于多弯曲模组，实现弯管的二次弯曲。在弯管的成形过程中，观察弯管的成形变化，包括弯管最外侧的减薄率及内侧的增厚率，同时在二次弯曲建模网格划分过程中，采用自适应网格技术，更加贴近实际地反映成形中应力应变的变化。在Ls-prepost中进行后处理，观察管壁减薄率等的变化。弯管的同曲率连续弯曲数值模拟结果有助于工程实际的应用，同时有限元方法有助于促进对弯管弯曲成形的研究。

英文摘要：

A method based on Ansys ls-dyna and Ls-prepost for numerically simulating con- tinuous secondary bending at the same curvature was proposed. The secondary bending was realized by using Ansys ls-dyna software and based on multi-bending die group. The forming change of the elbow pipe was observed during the forming process, including the thinning ratio at the most outboard of the elbow and medial thickening rate. The adaptive grid technology was applied during the division process of secondary bending modeling grid which can more realistically reflect the stress-strain change in forming. With the post-processing by Ls-prepost, the change of thinning ratio, etc can be observed.