Spatial shapes of magnetoelastic shear body waves at the transmission edges in a periodically inhomogeneous magnetostrictive medium

The spatial shapes of magnetoelastic shear body waves at the transmission edges in a periodically inhomogeneous magnetostrictive medium are studied. Numerical results are obtained for a two-component composition of ferrite and nonmagnetic dielectric __________ Translated from Prikladnaya Mekhanika, Vol. 42, No. 3, pp. 61–69, March 2006.     

Magnetoelastic shear body waves in periodically inhomodeneous media

The shapes of magnetoelastic shear body waves in periodically inhomogeneous magnetostrictive dielectric media are studied with emphasis on wave shapes in the neighborhood of the zones of interaction of elastic and magnetostatic waves __________ Translated from Prikladnaya Mekhanika, Vol. 42, No. 10, pp. 13–20, October 2006.     

Acoustoelectric shear body waves in periodically layered metallized piezodielectric media

The paper proposes a technique to derive the dispersion relations for acoustoelastic shear body waves propagating in periodically layered media formed of identical metallized sandwiches, each consisting of two different piezoelectric layers and a dielectric layer between them. A numerical analysis is carried out and the propagation of body waves in different structures is described for a wide range of frequencies and wave numbers. The effect of the physical, mechanical, and geometrical parameters of the layers on the transmission and suppression bands is examined. The influence of the piezoeffect on the arrangement of the transmission edges upon change in the relative thickness of the layers is studied __________ Translated from Prikladnaya Mekhanika, Vol. 44, No. 7, pp. 61–67, July 2008.     

On shapes of body waves in periodically inhomogeneous, magnetostrictive, dielectric materials

The shapes of shear body waves in periodically inhomogeneous, magnetostrictive, dielectric media are studied with emphasis on the partial (elastic and magnetostrictive) wave motions coupled to produce magnetoelastic waves __________ Translated from Prikladnaya Mekhanika, Vol. 42, No. 7, pp. 57–63, July 2006.     

Propagation of Coupled Waves Interacting with an Electromagnetic Field in Periodically Inhomogeneous Media

The paper is concerned with coupled (electroelastic, electromagnetoelastic, and magnetoelastic) waves in inhomogeneous media     

Dispersion relations for electroelastic shear waves in a periodically layered medium

Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Prikladnaya Mekhanika, Vol. 26, No. 11, pp. 84–93, November, 1990.     

Propagation of Elastic Waves in Periodically Inhomogeneous Media

The structural theory of waves and vibrations in periodically inhomogeneous media is set out. Relevant research results are presented. Emphasis is on the principles of the theory, surface waves, and other surface effects     

Dispersion equation of magnetoelastic shear waves in irregular monoclinic layer

This paper studies the propagation of horizontally polarized shear waves in an internal magnetoelastic monoclinic stratum with irregularity in lower interface. The stratum is sandwiched between two magnetoelastic monoclinic semi-infinite media. Dispersion equation is obtained in a closed form. In the absence of magnetic field and irregularity of the medium, the dispersion equation agrees with the equation of classical case in three layered media. The effects of magnetic field and size of irregularity on the phase velocity are depicted by means of graphs.     

Propagation of magnetoelastic stress waves from a cylindrical cavity in a conducting medium

We study the influence of a constant axial magnetic field on the propagation of magnetoelastic compression waves from a cavity containing a magnetoacoustic medium with a jump of the surface force given at the wall. The problem is examined in [1] in the case in which there is a vacuum in the cavity and an ideal conductor outside, without any study of the effect of a magnetic field.Here we examine the problem for both weak and ideal conductivities. The equations are linearized and Laplace transformed. Approximate asymptotic solutions are constructed which are valid in the vicinity of the wave fronts. The solutions are studied analytically and numerically.In conclusion the author wishes to thank Ya. S. Uflyand for discussions of certain questions.     

Propagation of nonlinear waves in an inhomogeneous gas-liquid medium. Derivation of wave equations in the Korteweg-de Vries approximation

Equations describing the propagation of waves of small but finite amplitude in a liquid with gas bubbles are derived. The bubble distribution density is a continuous function of bubble size and spatial coordinates. It is found that, for a uniform bubble distribution, the obtained equations become the Korteweg-de Vries, Kadomtsev-Petviashvili and Khokhlov-Zabolotskaya equations. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 50, No. 2, pp. 188–197, March–April, 2009.     

波在双孔隙与单孔隙介质界面上的反射与透射

基于Biot理论和双重孔隙介质理论研究了弹性波在双重孔隙介质与流体饱和单一孔隙介质 界面的反射和透射问题,在界面上假定裂缝孔隙流体相对于固体骨架的位移为零,推导了反 射系数和透射系数的计算公式,数值讨论了反射系数和透射系数随入射角和频率的变化关 系. 同时,讨论了双重孔隙介质中3种压缩波(P-1, P-2和P-3波)和一种剪切波(S波) 的频散和衰减特性.     

各向异性粘弹性多孔截止中平面波的传播

This study discusses wave propagation in perhaps the most general model of a poroelastic medium. The medium is considered as a viscoelastic, anisotropic and porous solid frame such that its pores of anisotropic permeability are filled with a viscous fluid. The anisotropy considered is of general type, and the attenuating waves in the medium are treated as the inhomogeneous waves. The complex slowness vector is resolved to define the phase velocity, homogeneous attenuation, inhomogeneous attenuation, and angle of attenuation for each of the four attenuating waves in the medium. A non-dimensional parameter measures the deviation of an inhomogeneous wave from its homogeneous version. An numerical model of a North-Sea sandstone is used to analyze the effects of the propagation direction, inhomogeneity parameter, frequency regime, anisotropy symmetry, anelasticity of the frame, and viscosity of the pore-fluid on the propagation characteristics of waves in such a medium.     

Analogy between antiplane shear waves in anisotropic and isotropic media

A linear transformation is presented that transforms the fundamental equations of antiplane shear waves in an anisotropic medium into those of an isotropic medium. By this transformation, the solution of the former problem may be easily obtained if the corresponding latter problem has been solved.     

Propagation of Magnetoelastic Shear Waves Through a Regularly Laminated Medium with Metallized Interfaces

An exact solution is found for magnetoelastic shear waves in an infinite structure consisting of three metallized layers. The core layer is ferrite and the face layers are nonmagnetic dielectrics. The wave process in the layers is described by a linearized system of magnetoelastic equations. The problem posed is reduced to a system of linear algebraic equations. The existence conditions for an undamped solution to this system yield the existence conditions for magnetoelastic bulk waves. The dispersion relations derived are analyzed in detail     

Surface Magnetoelastic Shear Waves in Periodic Ferrite-Dielectric Regularly Stratified Structures

Surface magnetoelastic Love waves in a regularly stratified medium with ferrite and dielectric layers are studied based on the Hamilton formalism and numerical procedures. The dispersion relations are analyzed for particular structures     

非均匀损伤介质中波传播的数值解

对弹性波在非均匀损伤介质中的传播理论进行了研究。通过将非均匀损伤区域离散成分层均匀的区域,结合相邻区域交界面处的连续条件,推导出了以右行波、左行波为状态向量的波动方程和传递矩阵。对几种非均匀损伤介质中波的传播进行了实例数值计算,并和其解析解的结果进行了比较,讨论了弹性波在非均匀损伤介质中传播的一般性质。