低速冲击下复合材料刚退化方案仿真研究

精品文档---下载后可任意编辑伊鹏跃，于哲峰，汪海（上海交通大学 航空航天学院，上海 202440 ）摘要：针对复合材料层压板低速冲击仿真，根据应力更新、材料弹性参数折减和基于应变渐进失效的不同刚度退化思路，改进传统损伤刚度折减方法，通过 ABAQUS 分别编写了三种刚度退化方案的 VUMAT 子程序，引入粘滞规律克服刚度退化的数值计算收敛困难，结合实验进行有限元仿真，讨论比较了不同刚度退化方案下冲击响应的异同，结果表明：改进的三种刚度退化方案都可较准确地描述低速冲击下复合材料失效过程；应力更新方案，思路简单清楚，但失效过程应力变化剧烈，增量步数多，计算效率低；弹性参数折减方案中，根据失效模式调整折减系数，结合粘滞规律，响应平稳；前两种方案对冲击损伤形式只能定性，无法定量表征；而渐进失效方案引入合理的损伤变量，不但冲击响应连续而且能较好地表征材料损伤形式与程度。关键词：复合材料 低速冲击 刚度退化 VUMAT 有限元Stiffness degradation simulation methodsfor composite laminatesubjected tolow-velocity impactYI Pengyue,YU Zhefeng,WANG Hai(School of Aeronautics and Astronautics,ShanghaiJiaoTongUniversity,Shanghai 202440,China)Abstract:To studysimulation of composite laminate under low-velocity impact,stiffness reductionstrategies based onstress updating,degradation of elastic constant and progressive damage have been modified and implemented in the user material subroutine (VUAMT) in ABAQUS. The difficulty of convergence in numerical calculation is overcome by viscous regularization.Differences between the three methods have been studied according to the finite element analysis and experimentaldata. Conclusions drawn from the comparisonare that,the analytical results are ideal compared to test results.The three stiffness degradation process can describe the process of material damage exactly.Solution based on stress updating is simple and clear，but the number of increment and iteration is large due to stress varying greatly during material damage and computer calcul...