摘要
基于自动铺丝工艺,为获得良好的蜂窝夹层结构自动铺放成型质量,建立了Nomex蜂窝芯在压辊压力下的屈曲、后屈曲和破坏整个失效过程的数值分析方法。采用线性屈曲分析法(特征值分析法)对蜂窝单元进行屈曲分析,得到一阶屈曲模态、屈曲特征值及屈曲载荷;引入初始结构几何缺陷,采用非线性屈曲分析法(弧长法)对Nomex蜂窝单元后屈曲行为进行分析,输出参考点RP-1的载荷-位移曲线,得到弧长法计算的屈曲载荷以及极限载荷值。通过对比试验结果与两种屈曲分析法得到:对于分析临界屈曲载荷,特征值法较弧长法更精确;而弧长法可以更好模拟结构的后屈曲行为,计算结果与试验数据基本吻合,为Nomex蜂窝夹心结构自动铺放成型过程中铺放压力的选取提供参考。
In order to obtain a good honeycomb sandwich structure automatic placement quality,based on the automated fiber placement a numerical method for buckling,post-buckling and failure of Nomex honeycomb cores under compression load are established. The linear buckling method(eigenvalue method) is used to analyze buckling of honeycomb cell and the first -order buckling mode,the buckling eigenvalue and load are obtained. The initial geometrical defects are introduced,and non-linear buckling method(arc length method) is used to analyze the post-buckling behavior of Nomex honeycomb cell. According to the load-displacement curve of RP-1,the buckling load and the limit load of the arc length method are obtained. Contrasting the data of the finite element bucking analysis and experiment,some conclusions can be obtained:The eigenvalue method is more accurate than the arc length method in buckling analysis,but the arc length method can simulate post - buckling behavior better. The calculated results are basically consistent with the experimental data. A reference is provided for selecting the placement pressure in the process of automatic placement of Nomex honeycomb sandwich structure.
作者
窦明月
王显峰
张冬梅
赵聪
肖军
徐福泉
DOU Mingyue;WANG Xianfeng;ZHANG Dongmei;ZHAO Cong;XIAO Jun;XU Fuquan(College of Materials Science and Technology,Nanjing University of Aeronautics & Astronautics, Naijing,210016,China;Shanghai Aircraft Manufacturing Co.,Ltd,Shanghai,200436,China;Aviation Industry Harbin Aircraft Industry Group Co.,Ltd,Harbin,150066,China)
出处
《南京航空航天大学学报》
EI
CAS
CSCD
北大核心
2019年第1期69-74,共6页
Journal of Nanjing University of Aeronautics & Astronautics
基金
国家重点基础研究发展计划("九七三"计划)(2014CB046501)资助项目
"高档数控机床与基础制造装备"科技重大专项(2017ZX04009001)资助项目
关键词
自动铺丝成型
Nomex蜂窝芯
屈曲
后屈曲
特征值法
弧长法
automated fiber placement
Nomex honeycomb core
buckling
post - buckling
eigenvalue method
arc length method
