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Peijun Wei - One of the best experts on this subject based on the ideXlab platform.
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wave propagation through a piezoelectric semiconductor slab sandwiched by two piezoelectric Half Spaces
European Journal of Mechanics A-solids, 2019Co-Authors: Fengyu Jiao, Peijun Wei, Yahong Zhou, Xiaoli ZhouAbstract:Abstract The paper analyses the wave propagation through a piezoelectric semiconductor slab sandwiched by two piezoelectric Half-Spaces. The two piezoelectric Half-Spaces (left and right) are both AlN materials, the middle piezoelectric semiconductor slab is ZnO material and is assumed to be transversely isotropic. The semiconductor effect is emphasized by considering the coupling mechanical displacement, electric potential and the carrier in the slab. The state transition differential equation is derived based on the reduction of order of the governing equations and the transfer matrix of state is obtained by solving the state transition equation. The present method can deal with not only the homogeneous slab but also the heterogeneous slab. Two cases (incident QP wave and incident QSV wave) are considered, and the energy reflection and transmission coefficients varying with the incident angle are calculated. The results show that the steady carrier density and the exterior biasing electric field have obvious influences on the reflection and transmission coefficients. This investigation provides a new thought for the adjustment and controlling of elastic wave propagation in the laminated structures.
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wave propagation through a flexoelectric piezoelectric slab sandwiched by two piezoelectric Half Spaces
Ultrasonics, 2018Co-Authors: Fengyu Jiao, Peijun WeiAbstract:Reflection and transmission of plane waves through a flexoelectric piezoelectric slab sandwiched by two piezoelectric Half-Spaces are studied in this paper. The secular equations in the flexoelectric piezoelectric material are first derived from the general governing equation. Different from the classical piezoelectric medium, there are five kinds of coupled elastic waves in the piezoelectric material with the microstructure effects taken into consideration. The state vectors are obtained by the summation of contributions from all possible partial waves. The state transfer equation of flexoelectric piezoelectric slab is derived from the motion equation by the reduction of order, and the transfer matrix of flexoelectric piezoelectric slab is obtained by solving the state transfer equation. By using the continuous conditions at the interface and the approach of partition matrix, we get the resultant algebraic equations in term of the transfer matrix from which the reflection and transmission coefficients can be calculated. The amplitude ratios and further the energy flux ratios of various waves are evaluated numerically. The numerical results are shown graphically and are validated by the energy conservation law. Based on these numerical results, the influences of two characteristic lengths of microstructure and the flexoelectric coefficients on the wave propagation are discussed.
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wave propagation through a micropolar slab sandwiched by two elastic Half Spaces
Journal of Vibration and Acoustics, 2016Co-Authors: Peng Zhang, Peijun WeiAbstract:The problem of wave propagation through a micropolar elastic slab sandwiched by two classical elastic Half-Spaces is studied in this paper. Different from the classical elastic solids, the particle in micropolar solids can bear not only the displacements but also the rotations. The additional kinetic freedom results in four kinds of wave modes, namely, the longitudinal displacement (LD) wave, the longitudinal microrotational (LR) wave, and two coupled transverse (CT) waves. Apart from the LD wave, the other three waves are dispersive. The existence of couple stresses and the microrotations also makes the interface conditions between the micropolar slab and the classic elastic Half-Spaces different from that between two classic solids. The nontraditional interface conditions lead to a set of algebraic equations from which the amplitude ratios of reflection and transmission waves can be determined. Further, the energy fluxes carried by various waves are evaluated and the energy conservation is checked to validate the numerical results obtained. The influences of the micropolar elastic constants and the thickness of slab are discussed based on the numerical results. Two situations of incident P wave and incident SH wave are both considered.
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reflection and transmission through a microstructured slab sandwiched by two Half Spaces
European Journal of Mechanics A-solids, 2016Co-Authors: Peijun WeiAbstract:Abstract The reflection and transmission of a plane wave through a microstructured slab sandwiched by two Half-Spaces are studied in this paper. First, the wave propagation in a micro-structured solid of the dipolar gradient elasticity is formulated. Then, the reflection and transmission properties of a plane wave through a micro-structured slab sandwiched by two Half-Spaces are considered. The nontraditional interfacial conditions by requiring the auxiliary monopolar tractions, the auxiliary dipolar tractions, the displacements and the normal derivative of displacements continuous across the two interfaces are used to determine the amplitude ratio. The energy fluxes carried by various waves and the reflection and transmission coefficients in terms of energy flux ratio with respect to incident wave are calculated numerically. Based on these numerical results, the microstructure effects on the reflection and transmission waves for the incident P wave and incident SH wave with different wavelength are discussed. In particular, the influences of three characteristic lengths, namely, the incident wavelength, the thickness of slab and the characteristic length of microstructure, on the reflection and transmission waves are analyzed. It is found that the microstructure effect results in the appearance of evanescent wave mode. The reflection and transmission coefficients are evidently dependent upon the microstructure parameters and become more pronounced when the incident wavelength is close to the characteristic length of microstructure.
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Influences of mechanically and dielectrically imperfect interfaces on the reflection and transmission waves between two piezoelectric Half Spaces
International Journal of Solids and Structures, 2015Co-Authors: Xiao Guo, Peijun Wei, Qiheng TangAbstract:The influences of mechanically and dielectrically imperfect interfaces on the reflection and transmission waves between two piezoelectric Half Spaces are studied in this paper. First, the secular equations in the traverse isotropic piezoelectric Half space are derived from the general dynamic equation. Then, six kinds of imperfect interfaces are considered. These imperfect interfaces include: the mechanically compliant, dielectrically weakly conducting imperfect interface; the mechanically compliant, dielectrically highly conducting imperfect interface; the grounded metallized interface and the low-dielectric interface and their mechanical counterpart, namely, the fixed interface and the slippery interface. These imperfect interface conditions are required to be satisfied by four sets of waves, namely, the quasi-longitudinal wave (QP), the quasi-transverse wave (QSV), the shear horizontal wave (SH) which is decoupled to other waves and the electric-acoustic wave (EA). The algebraic equations resulting from the imperfect interface conditions are solved to obtain the amplitude ratio of various waves and furthermore the reflection and transmission coefficients in terms of the energy flux ratio. The numerical results are obtained for the incident QP wave, the incident QSV wave and the incident SH wave and are validated by the energy conservation principle. The effects of these imperfect interfaces are discussed based on the numerical results. The present study provides useful information for the detection of imperfect interface. (C) 2015 Elsevier Ltd. All rights reserved.
S K Tomar - One of the best experts on this subject based on the ideXlab platform.
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waves at interface of dissimilar nonlocal micropolar elastic Half Spaces
Mechanics of Advanced Materials and Structures, 2019Co-Authors: Aarti Khurana, S K TomarAbstract:This work is concerned with reflection/transmission phenomena of plane waves at plane discontinuity separating the two distinct nonlocal micropolar solids in perfect contact. Two problems have been...
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transmission of shear waves through a self reinforced layer sandwiched between two inhomogeneous viscoelastic Half Spaces
International Journal of Mechanical Sciences, 2005Co-Authors: S Chaudhary, V P Kaushik, S K TomarAbstract:Abstract A problem of reflection and transmission of plane SH-wave through a perfectly conducting self-reinforced elastic layer interposed between two vertically inhomogeneous viscoelastic solid Half-Spaces has been studied in this paper. The heterogeneity in the Half-Spaces is taken exponentially varying along vertical direction. Expressions of reflection and transmission coefficients are obtained in closed form and it is found that these coefficients depend on the angle of incidence, inhomogeneity parameters of the Half-Spaces and on the reinforcement parameters of the sandwiched layer. These coefficients are computed for a specific model against the angle of incidence for different values of inhomogeneity parameters of the Half-Spaces and for reinforcement parameter of the layer. The results have been presented graphically. The problem studied by Borcherdt [Reflection and refraction of type-II SH waves in elastic and anelastic media. Bulletin of the Seismological Society of America 1977;67:43–67] has been reduced as a special case.
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reflection and refraction of sh waves at a corrugated interface between two laterally and vertically heterogeneous viscoelastic solid Half Spaces
International Journal of Solids and Structures, 2005Co-Authors: Jatinder Kaur, S K Tomar, V P KaushikAbstract:Abstract Reflection and transmission coefficients due to incident plane SH-waves at a corrugated interface between two isotropic, laterally and vertically heterogeneous visco-elastic solid Half Spaces are obtained. The density and complex rigidity of each medium are considered to vary along horizontal and vertical directions. Closed form expressions of reflection and transmission coefficients are derived using Rayleigh’s method of approximation. These coefficients are found to be the function of corrugation, heterogeneity, angle of incidence, angle between propagation and attenuation vectors and visco-elasticity of the media. Numerical computations are made for a specific model to study the nature of dependence of these coefficients. Variations of reflection and transmission coefficients for the first order of approximation of the corrugation versus angle of incidence, corrugation and angle between propagation and attenuation vectors are computed and depicted graphically. Comparison is made between these coefficients in viscoelastic media and in uniform elastic media. The problems investigated earlier by Asano [Bull. Earthq. Res. Inst. 38 (1960) 177], Singh et al. [Acta Geophys. Pol. XXVI (1978) 209], Kaushik and Chopra [Geophys. Res. Bull. 18 (1980) 111] and Gupta [Geophys. Trans. 33 (1987) 89] have been reduced as particular cases.
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reflection and transmission of waves from a plane interface between two microstretch solid Half Spaces
International Journal of Engineering Science, 2005Co-Authors: S K Tomar, Monika GargAbstract:In this paper, we have investigated the wave propagation and their reflection and transmission from a plane interface between two different microstretch elastic solid Half-Spaces in perfect contact. It is shown that there exist five waves in a linear homogeneous isotropic microstretch elastic solid, one of them travel independently, while other waves are two sets of two coupled waves. It is also shown that these waves travel with different velocities, three of which disappear below a critical frequency. Amplitude ratios and energy ratios of various reflected and transmitted waves are presented when a set of coupled longitudinal waves and a set of coupled transverse waves is made incident. It is found that the amplitude ratios of reflected and transmitted waves are functions of angle of incidence, frequency and are affected by the elastic properties of the media. Some special cases have been reduced from the present formulation.
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reflection transmission of plane sh wave through a self reinforced elastic layer between two Half Spaces
Acta Geophysica Polonica, 2004Co-Authors: S Chaudhary, V P Kaushik, S K TomarAbstract:The reflection and transmission of plane SH wave through a self-reinforced elastic layer sandwiched between two homogeneous visco-elastic solid Half-Spaces has been studied. The expressions for reflection and transmission coefficients are obtained. These coefficients are computed against the angle of incidence, normalized wave number and the reinforced parameters. The results obtained have been presented graphically. The problem studied by Borcherdt has been reduced as a special case of our problem. It is found that reflection and transmission coefficients depend on the angle of incidence, normalized wave number and the reinforcement parameters of the sandwiched layer.
V P Kaushik - One of the best experts on this subject based on the ideXlab platform.
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transmission of shear waves through a self reinforced layer sandwiched between two inhomogeneous viscoelastic Half Spaces
International Journal of Mechanical Sciences, 2005Co-Authors: S Chaudhary, V P Kaushik, S K TomarAbstract:Abstract A problem of reflection and transmission of plane SH-wave through a perfectly conducting self-reinforced elastic layer interposed between two vertically inhomogeneous viscoelastic solid Half-Spaces has been studied in this paper. The heterogeneity in the Half-Spaces is taken exponentially varying along vertical direction. Expressions of reflection and transmission coefficients are obtained in closed form and it is found that these coefficients depend on the angle of incidence, inhomogeneity parameters of the Half-Spaces and on the reinforcement parameters of the sandwiched layer. These coefficients are computed for a specific model against the angle of incidence for different values of inhomogeneity parameters of the Half-Spaces and for reinforcement parameter of the layer. The results have been presented graphically. The problem studied by Borcherdt [Reflection and refraction of type-II SH waves in elastic and anelastic media. Bulletin of the Seismological Society of America 1977;67:43–67] has been reduced as a special case.
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reflection and refraction of sh waves at a corrugated interface between two laterally and vertically heterogeneous viscoelastic solid Half Spaces
International Journal of Solids and Structures, 2005Co-Authors: Jatinder Kaur, S K Tomar, V P KaushikAbstract:Abstract Reflection and transmission coefficients due to incident plane SH-waves at a corrugated interface between two isotropic, laterally and vertically heterogeneous visco-elastic solid Half Spaces are obtained. The density and complex rigidity of each medium are considered to vary along horizontal and vertical directions. Closed form expressions of reflection and transmission coefficients are derived using Rayleigh’s method of approximation. These coefficients are found to be the function of corrugation, heterogeneity, angle of incidence, angle between propagation and attenuation vectors and visco-elasticity of the media. Numerical computations are made for a specific model to study the nature of dependence of these coefficients. Variations of reflection and transmission coefficients for the first order of approximation of the corrugation versus angle of incidence, corrugation and angle between propagation and attenuation vectors are computed and depicted graphically. Comparison is made between these coefficients in viscoelastic media and in uniform elastic media. The problems investigated earlier by Asano [Bull. Earthq. Res. Inst. 38 (1960) 177], Singh et al. [Acta Geophys. Pol. XXVI (1978) 209], Kaushik and Chopra [Geophys. Res. Bull. 18 (1980) 111] and Gupta [Geophys. Trans. 33 (1987) 89] have been reduced as particular cases.
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reflection transmission of plane sh wave through a self reinforced elastic layer between two Half Spaces
Acta Geophysica Polonica, 2004Co-Authors: S Chaudhary, V P Kaushik, S K TomarAbstract:The reflection and transmission of plane SH wave through a self-reinforced elastic layer sandwiched between two homogeneous visco-elastic solid Half-Spaces has been studied. The expressions for reflection and transmission coefficients are obtained. These coefficients are computed against the angle of incidence, normalized wave number and the reinforced parameters. The results obtained have been presented graphically. The problem studied by Borcherdt has been reduced as a special case of our problem. It is found that reflection and transmission coefficients depend on the angle of incidence, normalized wave number and the reinforcement parameters of the sandwiched layer.
Xiao Guo - One of the best experts on this subject based on the ideXlab platform.
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Influences of mechanically and dielectrically imperfect interfaces on the reflection and transmission waves between two piezoelectric Half Spaces
International Journal of Solids and Structures, 2015Co-Authors: Xiao Guo, Peijun Wei, Qiheng TangAbstract:The influences of mechanically and dielectrically imperfect interfaces on the reflection and transmission waves between two piezoelectric Half Spaces are studied in this paper. First, the secular equations in the traverse isotropic piezoelectric Half space are derived from the general dynamic equation. Then, six kinds of imperfect interfaces are considered. These imperfect interfaces include: the mechanically compliant, dielectrically weakly conducting imperfect interface; the mechanically compliant, dielectrically highly conducting imperfect interface; the grounded metallized interface and the low-dielectric interface and their mechanical counterpart, namely, the fixed interface and the slippery interface. These imperfect interface conditions are required to be satisfied by four sets of waves, namely, the quasi-longitudinal wave (QP), the quasi-transverse wave (QSV), the shear horizontal wave (SH) which is decoupled to other waves and the electric-acoustic wave (EA). The algebraic equations resulting from the imperfect interface conditions are solved to obtain the amplitude ratio of various waves and furthermore the reflection and transmission coefficients in terms of the energy flux ratio. The numerical results are obtained for the incident QP wave, the incident QSV wave and the incident SH wave and are validated by the energy conservation principle. The effects of these imperfect interfaces are discussed based on the numerical results. The present study provides useful information for the detection of imperfect interface. (C) 2015 Elsevier Ltd. All rights reserved.
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effects of initial stress on the reflection and transmission waves at the interface between two piezoelectric Half Spaces
International Journal of Solids and Structures, 2014Co-Authors: Xiao Guo, Peijun WeiAbstract:The effects of initial stress on the reflection and transmission waves at the interface between two piezoelectric Half Spaces are studied in this paper. First, the secular equations in the traverse isotropic piezoelectric Half space are derived from the general dynamic equation with initial stress taken into consideration. Then, the interface conditions that displacement, stress, electric potential, and electric displacement are continuous across interface are required to be satisfied by three sets of coupled waves, namely, quasi-longitudinal wave, quasi-transverse wave and the electric acoustic wave. The algebraic equations resulting from the interface conditions are solved to obtain the amplitude ratio of various waves and furthermore the energy reflection and transmission coefficients of various waves. The numerical results are shown graphically and the effects of initial stress are discussed. (C) 2014 Elsevier Ltd. All rights reserved.
S Chaudhary - One of the best experts on this subject based on the ideXlab platform.
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transmission of shear waves through a self reinforced layer sandwiched between two inhomogeneous viscoelastic Half Spaces
International Journal of Mechanical Sciences, 2005Co-Authors: S Chaudhary, V P Kaushik, S K TomarAbstract:Abstract A problem of reflection and transmission of plane SH-wave through a perfectly conducting self-reinforced elastic layer interposed between two vertically inhomogeneous viscoelastic solid Half-Spaces has been studied in this paper. The heterogeneity in the Half-Spaces is taken exponentially varying along vertical direction. Expressions of reflection and transmission coefficients are obtained in closed form and it is found that these coefficients depend on the angle of incidence, inhomogeneity parameters of the Half-Spaces and on the reinforcement parameters of the sandwiched layer. These coefficients are computed for a specific model against the angle of incidence for different values of inhomogeneity parameters of the Half-Spaces and for reinforcement parameter of the layer. The results have been presented graphically. The problem studied by Borcherdt [Reflection and refraction of type-II SH waves in elastic and anelastic media. Bulletin of the Seismological Society of America 1977;67:43–67] has been reduced as a special case.
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reflection transmission of plane sh wave through a self reinforced elastic layer between two Half Spaces
Acta Geophysica Polonica, 2004Co-Authors: S Chaudhary, V P Kaushik, S K TomarAbstract:The reflection and transmission of plane SH wave through a self-reinforced elastic layer sandwiched between two homogeneous visco-elastic solid Half-Spaces has been studied. The expressions for reflection and transmission coefficients are obtained. These coefficients are computed against the angle of incidence, normalized wave number and the reinforced parameters. The results obtained have been presented graphically. The problem studied by Borcherdt has been reduced as a special case of our problem. It is found that reflection and transmission coefficients depend on the angle of incidence, normalized wave number and the reinforcement parameters of the sandwiched layer.
