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1.
In this study, Fabrikant (1989, 1991)'s new results in potential theory were used to obtain the exact and complete solution
for the problem of a penny-shaped crack in an infinite transversely isotropic piezoelectric body subjected to antisymmetric
point loads (point charges and normal point forces); then the complete solution for the problem of one-sided loading of a
penny-shaped crack was obtained by the superposition of the symmetric loading solution in Chen and Shioya (1999) and the antisymmetric
one presented here; and then the reciprocity theorem of piezoelectric media was used to deal with the problem of interaction
between arbitrarily located point forces and a point charge with a penny-shaped crack and obtained the exact expressions of
the crack faces' normal displacement in terms of elementary functions and some non-singular integrals; and finally obtained
the normal displacement of the positive and negative faces of the crack under many loading cases as shown in figures for an
infinite PZT-4 piezoelectric ceramic body weakened by a penny-shaped crack.
Project (19872060) supported by the Natural Science Foundation of China. 相似文献
2.
EXACT SOLUTION OF AN EXTERNAL CIRCULAR CRACK IN A PIEZOELECTRIC SOLID SUBJECTED TO SHEAR LOADING 总被引：4，自引：0，他引：4
ＩＮＴＲＯＤＵＣＴＩＯＮＤｕｅｔｏｔｈｅｉｎｈｅｒｅｎｔｗｅａｋｎｅｓｓｏｒｂｒｉｔｔｌｅｎｅｓｓｏｆｐｉｅｚｏｅｌｅｃｔｒｉｃｃｅｒａｍｉｃｓ,ｔｈｅｆｒａｃｔｕｒｅｏｆｐｉｅｚｏ ｅｌｅｃｔｒｉｃｍａｔｅｒｉａｌｓｈａｓｇａｉｎｅｄｃｏｎｓｉｄｅｒａｂｌｅｉｎｔｅｒ ｅｓｔ.Ｍｏｓｔｐｕｂｌｉｓｈｅｄｗｏｒｋｓｄｅａｌｔｗｉｔｈｔｗｏ ｄｉｍｅｎ ｓｉｏｎａｌｓｔｕｄｙｏｆｃｒａｃｋｓｉｎｐｉｅｚｏｅｌｅｃｔｒｉｃｍａｔｅｒｉａｌｓ(Ｐａｋ ,1 990 ;Ｓｕｏｅｔａｌ.,1 992 ;ＺｈｏｎｇａｎｄＭｅｇｕｉ… 相似文献
3.
A three-dimensional, exact analysis is presented in this paper for the problem of an external circular crack in a transversely
isotropic piezoelectric medium subjected to arbitrary antisymmetric shear loading. A recently proposed general solution of
three-dimensional piezoelectricity is employed. It is shown that four quasi harmonic functions involved in the general solution
can be respresented by just one complex potential. Previous results in potential theory are then used to obtain the exact
solution of the problem. For point shear loading, Green’s functions for the elastoelectric field are derived in terms of elementary
functions.
Project supported by Scientific Research Foundation for Returned Overseas Chinese Scholars, State Education Ministry and partly
by National Natural Science Foundation of China (NSFC) (10002016). 相似文献
4.
INTRODUCTION In isotropic elasticity a class of mixed boundary value problems for elastic half-space can be classified as axisymmetric torsion. In this case the elastic field in cylinder components takes a particularly simple form consisting of only one nonzero displacement and two nonzero stress components. For this loading case, Reissner and Sagoci (1944) were possibly the first to examine a mixed boundary problem between the tangential displacement and stress on the half-space surface.… 相似文献
5.
黄上恒 《商丘师范学院学报》2000,16(4):36-38
研究了同时处于机械与电学载荷之下的压电陶瓷柱体表面裂纹前缘的应力场和电位移场。求得了应力及电位移的奇异性阶数和相应的两个强度因子。 相似文献
6.
INTRODUCTION Piezoelectric bimorphs (or benders), a special type of piezoelectric device, which can produce flexural deformation significantly larger than the length or thickness deformation of the individual piezoelectric layers, have been widely used as elec- troacoustic transducers, medical devices and micro- robot due to their characteristics of easy miniaturiza- tion, high positioning accuracy, sensitive response, and large displacement (e.g., Shirley and Hampton, 1978; Ha and Kim, 2… 相似文献
7.
Yang Gao 《浙江大学学报(A卷英文版)》2010,11(10):835-840
This paper deals with the combination of point phonon and phason forces applied in the interior of infinite planes and half-planes of 1D quasicrystal bi-materials. Based on the general solution of quasicrystals, a series of displacement functions are adopted to obtain Green＇s functions for infinite planes and bi-material planes composed of two half-planes in the closed form, when the two half-planes are supposed to be ideally bonded or to be in smooth contact. Since the physical quantities can be readily calculated without the need of performing any transform operations, Green＇s functions are very convenient to be used in the study of point defects and inhomogeneities in the quasicrystal materials. 相似文献
8.
The concept of eigen crack opening displacement (COD) can be defined as the COD of a crack in infinite plate under the tractions acting on the crack surface. By introducing this concept, the eigen COD formulation of boundary integral equation is proposed in this paper, together with the solution procedures for multiple crack problems in plane elasticity. With the proposed approach, the multiple crack problems can be solved with the conventional displacement discontinuity boundary integral equations in an it... 相似文献
9.
INTRODUCTION Recently, more and more investigations have been conducted on multilayer piezoelectric media. Kharouf and Heyliger (1994) and Heyliger and Ra- mirez (2000) dealt with the free vibration problems of laminated piezoelectric cylinders and discs, respec- tively. Chen (2000) considered the free vibration of (multilayer) nonhomogeneous piezoceramic hollow spheres by employing a separation formulation for displacements. Chen (2001) developed a state-space method for free vibration … 相似文献
10.
We made a theoretical study of the carrier distribution and electromechanical fields in a free piezoelectric semiconductor rod of crystals of class 6 mm. Simple analytical expressions for the carrier distribution, electric potential, electric field, electric displacement, mechanical displacement, stress, and strain were obtained from a 1D nonlinear model reduced from the 3D equations for piezoelectric semiconductors. The distribution and fields were found to be either symmetric or antisymmetric about the center of the rod. They are qualitatively the same for electrons and holes. Numerical calculations show that the carrier distribution and the fields are relatively strong near the ends of the rod than in its central part. They are sensitive to the value of the carrier density near the ends of the rod. 相似文献
11.
讨论了无限长功能梯度压电板中双裂纹尖端热响应分析,用Fourier积分变换把混合边值问题转化为以裂纹面上位移为未知量的对偶积分方程,利用Schmidt方法对其求解,最后通过数值算例考察了温度变化及材料系数对应力强度因子的重要影响. 相似文献
12.
从两点到三点到m点再到无穷多点,对常微分方程边值问题的研究最早始于牛顿和莱布尼茨建立微积分的最初阶段。这些常微分方程多点边值问题也常常被称为常微分方程非局部问题。讨论阶数为q∈（1,2）的非线性分数阶微分方程四点非局部边值问题,借助Ascoli—Arzela定理,首先利用压缩映射原理得到解的唯一性,其次利用Krasnoselskii不动点定理得到四点边值问题至少存在一个解,并且举例验证。 相似文献
13.
With the terms of the exact series solution taken as trial functions, the method of point collocation was used to calculate the large deflection of a circular plate. The axisymmetrical bending formulae were developed for the calculation of a circular plate subjected to polynomial distributed loads, a concentrated load at the center, uniform radial forces and moments along the edge or their combinations. The support may be elastic. The buckling load was calculated. Under action of uniformly distributed load, central load or their compound load, solutions were compared with those obtained by other methods, Buckling beyond critical thrust was compared with that calculated by the power series method. The method presented in this paper has advantages of wide convergent range, high precision and short computing time. Moreover, the computing time is nearly independent of the complexity of the loads. 相似文献
14.
SINGH Bhupinder SINGH S.P KAUSHIK S.K. 《浙江大学学报(A卷英文版)》2007,8(2):257-263
INTRODUCTION Finite Element (FE) procedures are at present widely used in engineering modelling and analysis and employed extensively in the analysis of solids and structures and heat transfer and fluids (Bathe, 1996). The essence of FE solution of an engineering problem is that a set of governing algebraic equations is es-tablished which are then solved with the help of a digital computer. The first practical FE procedures were employed in linear analysis of solids and struc-tures (B… 相似文献
15.
赵晓东 《邢台职业技术学院学报》2004,21(1):33-34
本文讨论了数控机床归基准点的问题。详细讨论了数控机床归基准点的工作原理、常见方法及可能出现的故障，并分析了故障原因，给出了解决办法。 相似文献
16.
Wang Deren Zhao Fengguang 《上海大学学报(英文版)》1998,2(1):15-21
ＡＣｌａｓｏｆＩｔｅｒａｔｉｏｎＭｅｔｈｏｄｆｏｒｔｈｅＢｅｓｔＡｐｐｒｏｘｉｍａｔｉｏｎＰｒｏｂｌｅｍｓＷａｎｇＤｅｒｅｎＺｈａｏＦｅｎｇｇｕａｎｇ（ＣｏｌｅｇｅｏｆＳｃｉｅｎｃｅｓ）ＡｂｓｔｒａｃｔＷｅｐｒｏｐｏｓｅａｃｌａｓｓｏｆｉｔｅｒａｔｉ... 相似文献
17.
18.
INTRODUCTIONDuetotheirwideapplicationsinengineer ing ,piezoelectriccrystalplatesattractedmuchattentionandhadbeenextensivelystudiedasre ported .However,mostworkswerebasedonva rioustwo dimensionalapproximations (Dokmeci,1 980 ;Lawson ,1 942 ;Mindlin ,1 952 … 相似文献
19.
General solutions for coupled three dimensional equations of piezoelectric media were used in this work to obtain some analytical
solutions for free vibration of piezoelectric annular plates. These solutions not only satisfy the governing equations at
every point in the concerned region but also satisfy the prescribed boundary conditions at every point on the boundaries.
Therefore, they are three-dimensional exact. Numerical results are finally tabulated.
Project (No. 10002016) supported by the National Natural Science Foundation of China 相似文献
20.
We studied the problem of bifurcation and chaos in a 4-side fixed rectangular thin plate in electromagnetic and mechanical fields. Based on the basic nonlinear electro-magneto-elastic motion equations for a rectangular thin plate and the expressions of electromagnetic forces, the vibration equations are derived for the mechanical loading in a steady transverse magnetic field. Using the Melnikov function method, the criteria are obtained for chaos motion to exist as demonstrated by the Smale horseshoe mapping. The vibration equations are solved numerically by a fourth-order Runge-Kutta method. Its bifurcation diagram, Lyapunov exponent diagram, displacement wave diagram, phase diagram and Poincare section diagram are obtained. 相似文献