含内埋矩形脱层复合材料圆柱壳屈曲分析的混合变量条形传递函数方法

提出了一种分析含内埋矩形脱层正交各向异性圆柱壳稳定性问题的混合变量条形传递函数方法。首先基于Mindlin一阶剪切壳理论，通过定义圆柱壳的广义力变量和混合变量，建立了壳的改进混合变量能量泛函；然后，为了便于脱层壳的分区求解，通过引入条形单元，创建了基于混合变量条形传递函数解的含脱层和不合脱层两种超级壳单元；在此基础上，将含内埋矩形脱层的复合材料层合壳划分成两种超级壳单元的组合体，通过各超级壳单元相互之间连接结点处的位移连续和力平衡条件得到脱层壳的屈曲方程；最后由屈曲方程计算含内埋矩形脱层壳的屈曲载荷和屈曲模态。算例分析的结果验证了本方法的正确性，并给出了几种因素对屈曲载荷和屈曲模态的影响。

Buckling analysis of composite cylindrical shell with built-in rectangular delamination by mixed variables strip transfer function method

In the engineering application of a composite cylindrical shell, the local patch-shaped delaminations, which can be simulated with rectangular or circular delaminations, are easy to emerge. In this paper, a mixed variables strip transfer function method is presented for analyzing the stability problem of orthotropic cylindrical shell with built-in rectangular delaminations. First, based on Mindlin's shell theory, the improved energy function with mixed variables for cylindrical shell is established by defining generalized force variables and mixed state variables. Then, in order to solve the problem of delaminated shell with separated-region method conveniently, based on a mixed variables strip transfer function method, two kinds of super shell elements with or without delamination are established by introducing strip elements. And based on these super shell elements, the characteristic equation for buckling analysis of laminated shell with built-in rectangular delamination is gotten by dividing the delaminated shell into several super shell elements and enforcing the displacement continuity and force balance at the inter-connecting nodes that connect each super shell element. Finally, buckling load and mode can be calculated from the characteristic equation. The results of numerical examples analysis valid the method in this paper and the influences of multi-factors on buckling load are presented.