共查询到18条相似文献,搜索用时 62 毫秒
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各向异性弹性层中SH波传播的边界元方法 总被引:1,自引:0,他引:1
本文利用坐标变换下的映象法求出了底部为刚性边界的各向异性弹性层中SH波传播问题的格林函数,并由此建立了求解分层介质问题的边界元方法。文中给出了在稳态线荷载作用下带有圆孔的弹性层中反应的计算实例。 相似文献
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本文探讨了瞬态SH波作用下单侧接触的结构-介质动相互作用问题。给出了瞬态边界元列式,利用迭代技术计算了接触面上的响应。计算表明接触摩擦对动力呼应有很大的影响。 相似文献
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Summary SH wave propagation in a cylindrically layered piezoelectric structure with initial stress is investigated analytically. By
means of transformation, the governing equations of the coupled waves are reduced to Bessel and Laplace equations. The boundary
conditions imply that the displacements, shear stresses, electric potential, and electric displacements are continuous across
the interface between the layer and the substrate. The electrically open and short conditions at the cylindrical surface are
applied to solve the problem. The phase velocity is numerically calculated for the electrically open and short cases, respectively,
for different wavenumber and thickness of the layer. The effect of the initial stress on the phase velocity and the electromechanical
coupling factor are discussed in detail for piezoelectric ceramics PZT-5H. We find that the initial stress has an important
effect on the SH wave propagation in the cylindrically layered piezoelectric structures. The results also show that the ratio
of the layer thickness to the wavelength has a remarkable effect on the SH wave phase velocity and electromechanical coupling
factor. 相似文献
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An exact approach is used to investigate the horizontally polarized shear wave in an irregular piezoelectric layer with corrugated surface lying over prestressed viscoelastic substrate. Perturbation technique is used to solve the problem. Dispersion relations are obtained in closed form for electrically open and short cases. The main feature of the present work is its ability to investigate the effect of irregularity, corrugation, dielectric constant, piezoelectric constant, initial stress and viscoelastic parameter on the phase velocity of SH wave. Numerical example has been carried out to observe the profound effect of these affecting parameters on phase velocity of SH wave. 相似文献
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This study is devoted to propagation of SH Waves (Shear Horizontal) in laminated elastic composite materials. Layers of material are perfectly bonded and reflection and transmission coefficients are given by transfer matrix method. Numerical results are pointed out through curves in which reflection and transmission coefficients are plotted versus incident angle. Composite materials with 3 and 10 layers are analysed at large and low wave-numbers compared with thickness of layers. We point out effects of frequency (or wave number) and of number of layers. Intending objective is to predict the quality of bonding by introducing elastic slip at interface between layers. 相似文献
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水平剪切(Shear Horizontal,SH)导波在传播的过程中有对称模式和反对称模式,其相速度和群速度主要取决于试件的厚度和频率之积(频厚积)。利用COMSOL有限元分析软件,建立了钢板缺陷的3-D模型,仿真分析了SH0导波在钢板中的传播特性。仿真结果表明SH波在传播过程中很少发生波束方向的改变,无频散和模式转换,信噪比高。利用电磁超声方法激励SH波,对钢板中的裂纹和焊缝缺陷进行了实验,验证了仿真结果的正确性及可行性,为超声导波在板材缺陷检测中的应用提供基础。 相似文献
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Bulk wave propagation in laminated piezomagnetic/piezoelectric plates with initial stresses and imperfect interface is investigated using the state space approach. Either electrically and magnetically open or shorted conditions on the top and bottom surfaces are considered. The phase velocity and frequency spectra of the wave are numerically calculated for various electric and magnetic conditions, and normalized modes are also analyzed. Although numerical results do indicate that the initial compressive stress can reduce the phase velocity of the wave propagating in a layered multiferroic structure, the effect is not as obvious as that reported in literature where the initial stresses were taken far beyond the strength of real materials. While the imperfect interface affect the frequency spectra much greater than initial stresses, because imperfection decreases the structural stiffness. 相似文献