The present paper is concerned with the wave propagation in a micropolar thermoelastic solid with distinct two temperatures under the effect of the magnetic field in the presence of the gravity field and an internal h...The present paper is concerned with the wave propagation in a micropolar thermoelastic solid with distinct two temperatures under the effect of the magnetic field in the presence of the gravity field and an internal heat source.The formulation of the problem is applied in the context of the three-phase-lag model and Green-Naghdi theory without dissipation.The medium is a homogeneous isotropic thermoelastic in the half-space.The exact expressions of the considered variables are obtained by using normal mode analysis.Comparisons are made with the results in the two theories in the absence and presence of the magnetic field as well as the two-temperature parameter.A comparison is also made in the two theories for different values of an internal heat source.展开更多
The thermoelastic interaction for the three-phase-lag (TPL) heat equation in an isotropic infinite elastic body with a spherical cavity is studied by two-temperature generalized thermoelasticity theory (2TT). The ...The thermoelastic interaction for the three-phase-lag (TPL) heat equation in an isotropic infinite elastic body with a spherical cavity is studied by two-temperature generalized thermoelasticity theory (2TT). The heat conduction equation in the theory of TPL is a hyperbolic partial differential equation with a fourth-order derivative with respect to time. The medium is assumed to be initially quiescent. By the Laplace trans- formation, the fundamental equations are expressed in the form of a vector-matrix differ- ential equation, which is solved by a state-space approach. The general solution obtained is applied to a specific problem, when the boundary of the cavity is subjected to the ther- mal loading (the thermal shock and the ramp-type heating) and the mechanical loading. The inversion of the Laplace transform is carried out by the Fourier series expansion tech- niques. The numerical values of the physical quantity are computed for the copper like ma- terial. Significant dissimilarities between two models (the two-temperature Green-Naghdi theory with energy dissipation (2TGN-III) and two-temperature TPL model (2T3phase)) are shown graphically. The effects of two-temperature and ramping parameters are also studied.展开更多
In the present article,we have used the three-phase-lag model of thermoelasticity to formulate a two dimensional problem of non homogeneous,isotropic,double porous media with a gravitational field im-pact.Thermal shoc...In the present article,we have used the three-phase-lag model of thermoelasticity to formulate a two dimensional problem of non homogeneous,isotropic,double porous media with a gravitational field im-pact.Thermal shock of constant intensity is applied on the bounding surface.The normal mode procedure is employed to derive the exact expressions of the field quantities.These expressions are also calculated numerically and plotted graphically to demonstrate and compare theoretical results.The influences of non-homogeneity parameter,double porosity and gravity on the various physical quantities are also ana-lyzed.A comparative study is done between three-phase-lag and GN-III models.Some limiting cases are also deduced from the current study.展开更多
The present article is concerned with the propagation of plane waves in a homogeneous,fiber-reinforced orthotropic thermoelastic ro-tating half-space in the context of three-phase-lag model.There exist three coupled w...The present article is concerned with the propagation of plane waves in a homogeneous,fiber-reinforced orthotropic thermoelastic ro-tating half-space in the context of three-phase-lag model.There exist three coupled waves,namely,quasi-longitudinal P-wave(qP),quasi-longitudinal thermal wave(qT)and quasi-transverse wave(qSV)in the medium.The reflection coefficients are computed numerically with the help of MATLAB programming and are depicted graphically to show the effects of rotation,fiber-reinforcement and phase lag parameters.The expressions of energy ratios have also been obtained in explicit form and are shown graphically as functions of angle of incidence.It has been verified that during reflection phenomena,the sum of energy ratios is equal to unity at each angle of incidence.Effect of anisotropy is depicted on velocities of various reflected waves.Some particular cases of interest have also been inferred from the present investigation.展开更多
The induced temperature, displacement, and stress fields in an infinite nonhomogeneous elastic medium having a spherical cavity are obtained in the context dual-phase-lag model. The surface of the cavity is stress fre...The induced temperature, displacement, and stress fields in an infinite nonhomogeneous elastic medium having a spherical cavity are obtained in the context dual-phase-lag model. The surface of the cavity is stress free and is subjected to a thermal shock. The material is elastic and has an in?homogeneity in the radial direction. The type of non homogeneity is such that the elastic constants, thermal conductivity and density are propor?tional to the nth power of the radial distance. The solutions are obtained analytically employing the Laplace transform technique. The numerical inversion of the transforms is carried out using Fourier series expansions. The stresses, temperature and displacement are computed and presented graphically. A comparison of the results for different theories is presented.展开更多
The present work is concerned with the solution of a problem on thermoelastic interactions in a functional graded material due to thermal shock in the context of the fractional order three-phase lag model. The governi...The present work is concerned with the solution of a problem on thermoelastic interactions in a functional graded material due to thermal shock in the context of the fractional order three-phase lag model. The governing equations of fractional order generalized thermoelasticity with three-phase lag model for functionally graded materials(FGM)(i.e., material with spatially varying material properties) are established. The analytical solution in the transform domain is obtained by using the eigenvalue approach.The inversion of Laplace transform is done numerically. The graphical results indicate that the fractional parameter has significant effects on all the physical quantities. Thus, we can consider the theory of fractional order generalized thermoelasticity an improvement on studying elastic materials.展开更多
文摘The present paper is concerned with the wave propagation in a micropolar thermoelastic solid with distinct two temperatures under the effect of the magnetic field in the presence of the gravity field and an internal heat source.The formulation of the problem is applied in the context of the three-phase-lag model and Green-Naghdi theory without dissipation.The medium is a homogeneous isotropic thermoelastic in the half-space.The exact expressions of the considered variables are obtained by using normal mode analysis.Comparisons are made with the results in the two theories in the absence and presence of the magnetic field as well as the two-temperature parameter.A comparison is also made in the two theories for different values of an internal heat source.
文摘The thermoelastic interaction for the three-phase-lag (TPL) heat equation in an isotropic infinite elastic body with a spherical cavity is studied by two-temperature generalized thermoelasticity theory (2TT). The heat conduction equation in the theory of TPL is a hyperbolic partial differential equation with a fourth-order derivative with respect to time. The medium is assumed to be initially quiescent. By the Laplace trans- formation, the fundamental equations are expressed in the form of a vector-matrix differ- ential equation, which is solved by a state-space approach. The general solution obtained is applied to a specific problem, when the boundary of the cavity is subjected to the ther- mal loading (the thermal shock and the ramp-type heating) and the mechanical loading. The inversion of the Laplace transform is carried out by the Fourier series expansion tech- niques. The numerical values of the physical quantity are computed for the copper like ma- terial. Significant dissimilarities between two models (the two-temperature Green-Naghdi theory with energy dissipation (2TGN-III) and two-temperature TPL model (2T3phase)) are shown graphically. The effects of two-temperature and ramping parameters are also studied.
文摘In the present article,we have used the three-phase-lag model of thermoelasticity to formulate a two dimensional problem of non homogeneous,isotropic,double porous media with a gravitational field im-pact.Thermal shock of constant intensity is applied on the bounding surface.The normal mode procedure is employed to derive the exact expressions of the field quantities.These expressions are also calculated numerically and plotted graphically to demonstrate and compare theoretical results.The influences of non-homogeneity parameter,double porosity and gravity on the various physical quantities are also ana-lyzed.A comparative study is done between three-phase-lag and GN-III models.Some limiting cases are also deduced from the current study.
文摘The present article is concerned with the propagation of plane waves in a homogeneous,fiber-reinforced orthotropic thermoelastic ro-tating half-space in the context of three-phase-lag model.There exist three coupled waves,namely,quasi-longitudinal P-wave(qP),quasi-longitudinal thermal wave(qT)and quasi-transverse wave(qSV)in the medium.The reflection coefficients are computed numerically with the help of MATLAB programming and are depicted graphically to show the effects of rotation,fiber-reinforcement and phase lag parameters.The expressions of energy ratios have also been obtained in explicit form and are shown graphically as functions of angle of incidence.It has been verified that during reflection phenomena,the sum of energy ratios is equal to unity at each angle of incidence.Effect of anisotropy is depicted on velocities of various reflected waves.Some particular cases of interest have also been inferred from the present investigation.
文摘The induced temperature, displacement, and stress fields in an infinite nonhomogeneous elastic medium having a spherical cavity are obtained in the context dual-phase-lag model. The surface of the cavity is stress free and is subjected to a thermal shock. The material is elastic and has an in?homogeneity in the radial direction. The type of non homogeneity is such that the elastic constants, thermal conductivity and density are propor?tional to the nth power of the radial distance. The solutions are obtained analytically employing the Laplace transform technique. The numerical inversion of the transforms is carried out using Fourier series expansions. The stresses, temperature and displacement are computed and presented graphically. A comparison of the results for different theories is presented.
文摘The present work is concerned with the solution of a problem on thermoelastic interactions in a functional graded material due to thermal shock in the context of the fractional order three-phase lag model. The governing equations of fractional order generalized thermoelasticity with three-phase lag model for functionally graded materials(FGM)(i.e., material with spatially varying material properties) are established. The analytical solution in the transform domain is obtained by using the eigenvalue approach.The inversion of Laplace transform is done numerically. The graphical results indicate that the fractional parameter has significant effects on all the physical quantities. Thus, we can consider the theory of fractional order generalized thermoelasticity an improvement on studying elastic materials.