功能梯度石墨烯增强多孔复合材料阶梯圆柱壳的振动特性

Vibration characteristics of functionally graded graphene reinforced porous composite stepped cylindrical shell

对功能梯度石墨烯增强多孔复合材料(FG-GPLRPC)阶梯圆柱壳的振动特性进行了研究。首先,采用Halpin-Tsai微观力学模型以及开胞体理论得到FG-GPLRPC阶梯圆柱壳的有效材料属性。其次,基于一阶剪切变形理论和惩罚参数法推导出壳体结构的能量表达式。最后,采用Jacobi-Ritz法建立壳体结构的振动控制方程,并求得结构的无量纲频率,验证了方法的有效性和正确性。结果表明,石墨烯质量分数、孔隙系数和边界弹簧刚度值对振动特性的影响显著,层数对振动特性的影响较小,尺寸参数对振动特性的影响不同,并得到了壳体频率随周向波数先减小后增大的变化规律。

Here,vibration characteristics of functionally graded graphene platelet reinforced porous composite(FG-GPLRPC)stepped cylindrical shell were studied.Firstly,effective material properties of FG-GPLRPC stepped cylindrical shell were obtained using Halpin-Tsai micromechanical model and the open-cell body theory.Secondly,based on the first-order shear deformation theory and the penalty parameter method,the energy expression of shell structure was derived.Finally,Jacobi-Ritz method was used to establish vibration governing equations of shell structure to solve dimensionless natural frequencies of shell structure,and verify the effectiveness and correctness of the proposed method.The results showed that mass fraction of graphene,pore coefficient and boundary spring stiffness value have a significant impact on vibration characteristics,while number of layers has a smaller impact on vibration characteristics;effects of size parameters on vibration characteristics are different;the variation law of shell natural frequencies decreasing firstly and then increasing with increase in circumferential wave number is obtained.