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本文将空间轴对称问题的Папковиц-Neuber通解用复变量广义解析函数表示,推导出用复变函数法求解空间轴对称问题的基本公式,并以此为工具求得了含球形空腔或刚性夹杂的中厚圆板在轴对称弯曲变形时的完全解. 相似文献
74.
In this paper, characteristics of the interface crack-tip stress and electric displacement fields in transversely isotropic piezoelectric bimaterials are studied. The authors have proven, within the framework of the generalized Stroh formalism for piezoelectric bimaterials, that there is no coexistence of the parameters (oscillating) and κ (non-oscillating) in the interface crack-tip generalized stress field for all transversely isotropic piezoelectric bimaterials. This leads to the classification of piezoelectric bimaterials into one group that exhibits the oscillating property in the interface crack-tip generalized stress field and the other that does not. Fifteen (15) pair-combinations of six (6) piezoelectric materials PZT-4, PZT-5H, PZT-6B, PZT-7A, P-7, and BaTiO3, which are commonly used in practice, are numerically analyzed in this study, and the results backup the above theoretical conclusions. Moreover, the associated eigenvectors for such material systems (with either =0 or κ=0) are also obtained numerically, and the result show that there still exist four linear independent associate eigenvectors for each bimaterial. 相似文献
75.
压电材料椭圆切口的力学分析 总被引:2,自引:3,他引:2
在线性压电本构方程框架下,用复势函数方法对椭圆切口模型进行了精确的数值计算。完整地考虑了各向异性力电耦合效应以及切口内不同电介质的介电性质。给出了切口内部不同介电性质对压电材料内部应力的影响。指出了Sosa文章里的一些计算错误。由于现在文献中很少有关于电导通边界条件下理论解的数值结果,所以本文同时提供了不同电边界条件下理论解的数值结果,所以本文同时提供了不同电边界条件下的理论解的数值结果。最后通过最小势能原理建立了8结点有限元模型,对椭圆切口问题进行了计算并与理论解进行了仔细比较。 相似文献
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V. I. Kushch 《International Applied Mechanics》2004,40(8):893-899
An elastic-equilibrium problem is rigorously solved for a transversely isotropic body containing a finite number of arbitrarily arranged and oriented transversely isotropic spherical inclusions or an infinite periodic array of such inclusions. The solution is found based on the superposition principle for general solutions of single-particle problems and the addition theorems for partial vector solutions of the elastic equilibrium equations. The numerical results presented allow assessing the influence of matrix anisotropy on the stress concentration between inclusions 相似文献
78.
A. V. Kozlov 《Fluid Dynamics》2004,39(1):162-167
Using the numerical method of direct statistical simulation (Monte-Carlo method), the effect of the intermolecular potential exponent on the dependence of the stress and the heat flux on the stress rate tensor components and the temperature gradient is analyzed for the nonequilibrium, spherically symmetric outflow of a monatomic gas into a vacuum. Analytical approximations of the constitutive relations are presented. The dependence of the macroscopic parameters on the distance from the source is found. 相似文献
79.
General coupled solution of anisotropic piezoelectric materials with an elliptic inclusion 总被引:1,自引:0,他引:1
In this investigation, the Stroh formalism is used to develop a general solution for an infinite, anisotropic piezoelectric
medium with an elliptic inclusion. The coupled elastic and electric fields both inside the inclusion and on the interface
of the inclusion and matrix are given.
The project supported by the National Natural Science Foundation of China 相似文献
80.
Functionally graded piezoelectric cantilever beam under load 总被引:3,自引:0,他引:3
Summary In the present paper, the problem of a functionally graded piezoelectric cantilever beam subjected to different loadings is studied. The piezoelectric beam is characterized by continuously graded properties for one elastic parameter and the material density. A pair of stress and induction functions in the form of polynomials is proposed and determined. Based on these functions, a set of analytical solutions for the beam subjected to different loadings is obtained. As particular cases, series of solutions for some canonical problems can be directly obtained from the solutions of the present paper, such as for the problems of a piezoelectric cantilever beam with constant body force or without body forces, etc.This research work is supported by the National Natural Science Foundation of China (50272003). Support was also given by the Teaching and Research Award Fund for Outstanding Young Teachers in Higher Education Institutions of MOE, P.R.C. 相似文献