Vibration and radial wave propagation velocity in functionally graded thick hollow cylinder
Vibration and radial wave propagation velocity in functionally graded thick hollow cylinder
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DOI：
10.1016/j.compstruct.2006.06.022
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发表时间：
2006-10
影响因子：
6.3
通讯作者：
M. Shakeri;M. Akhlaghi;S. M. Hoseini
中科院分区：
文献类型：
--
作者：
M. Shakeri;M. Akhlaghi;S. M. Hoseini
本文研究了功能梯度材料厚壁圆筒在动载荷作用下的动力响应。假设功能梯度柱体由多个子柱体组成。每个子柱被视为一个各向同性层。多层圆柱体中各层材料的性能是恒定的，通过合理的层间布置，可以实现材料的功能梯度特性。材料的性能受体积分数的控制，体积分数是半径的指数函数。假设壳体处于平面应变状态，并承受轴对称动力载荷。用Galerkin有限元法和Newmark法求解Navier方程。在两层之间的每个界面上，应力和位移满足连续性。利用快速傅立叶变换（FFT）将时间响应转换到频域，得到了结构的固有频率。然后讨论了功能梯度厚壁圆筒的动力学行为。研究了内压卸荷引起的径向波传播。讨论了径向应力随时间的变化规律，确定了不同n阶梯度材料径向应力波的平均传播速度。最后，假设功能梯度圆柱为各向同性，并将所得结果与解析结果进行了比较。
This article presents the analysis of functionally graded thick hollow cylinders under dynamic load. The functionally graded cylinder is assumed to be made of many subcylinders. Each subcylinder is considered as an isotropic layer. Material’s properties in each layer are constant and functionally graded properties are resulted by suitable arrangement of layers in multilayer cylinder. The properties are controlled by volume fraction that is an exponential function of radius. The shell is assumed to be in plane strain condition, and is subjected to axisymmetric dynamic loading. The Navier equation is solved by Galerkin finite element and Newmark methods. In each interface between two layers, stress and displacement continuity are satisfied. By using the fast Fourier transform (FFT), the time response is transfered to frequency domain and natural frequencies are illustrated. Then the dynamic behavior of functionally graded thick hollow cylinder is discussed. The radial wave propagation due to an internal pressure unloading is studied. The time history of radial stresses are discussed and the mean velocity of radial stress wave propagation for different exponent “n” of functionally graded material (FGM) are determined. Finally the functionally graded cylinder is assumed to be isotropic and the results are compared with the analytical results.