摘要
为了尽量降低摩擦的影响并提高膨胀管的缓冲吸能效率,在已有的两段圆弧式膨胀管变形理论模型的基础上,考虑管子弯曲和反弯曲曲率的变化对模型进行了修正,利用能量法和最小化膨胀力条件,对准静态下膨胀管的稳态膨胀力和成型后管径进行了预测。与有限元模拟结果相比,改进后的模型提高了对W-C模式膨胀管稳态膨胀力的预测精度,理论预测误差约25%~32%。但是该模型低估了摩擦对W-CC模式膨胀管的影响,且对于T-C模式膨胀管的稳态膨胀力和成型管径预测误差比较大。通过有限元模拟,讨论了不同变形模式膨胀管膨胀力的载荷特点,结果表明:W-CC模式膨胀管稳态膨胀力会随模具圆柱段长度的增大而增大;T-C模式膨胀管稳态膨胀力会随着加载而发生振荡,且振幅随模具锥角的增大而增大,但平均膨胀力受模具锥角增大的影响比较小。相比之下,W-C模式膨胀管稳态阶段膨胀力比较平稳,更适用于设计缓冲吸能结构。
In order to minimize the influence of friction and improve the buffer energy absorption efficiency of the expansion tube,the existing two-arcs deformational model is improved with considering the change of the bending curvature.Then the steady-state expansion force and the final radius of the expanded tubes can be obtained using energy conservation and the expansion force minimization.Compared with the finite element simulation results,the improved model improves the prediction accuracy of steady-state expansion force of W-C(tube wall-conical surface contact)mode expansion tubes,and the theoretical prediction error is about 25%-32%.However,this model underestimates the influence of friction on W-CC(tube wall-conical and cylindrical surface contact)mode expansion tubes,and the prediction error of steady-state expansion force and final radius of T-C(tube tip-conical surface contact)mode expansion tubes is large.The finite element simulation results show that the steady-state expansion force of W-CC mode expansion tubes increases with the increase of cylinder length of the die.The steady-state expansion force of T-C mode expansion tubes fluctuates and the amplitude increases with the increase of die angle,but the average expansion force in steady-state stage is less affected by the increase of die angle.In contrast,the steady-state expansion force of W-C mode expansion tubes is relatively stable,which is more suitable for designing energy absorption.
作者
虞晓欢
王波
何雨
YU Xiaohuan;WANG Bo;HE Yu(Institute of Fluid Physics,China Academy of Engineering Physics,Mianyang 621900,China)
出处
《机械工程师》
2025年第7期87-91,共5页
Mechanical Engineer
关键词
膨胀管
膨胀力
准静态
能量吸收
expansion tube
expansion load
quasi-static
energy absorption
作者简介
通信作者:虞晓欢(1989-),女,硕士,工程师,主要从事缓冲结构设计工作,oddcompass@163.com。
