scholarly journals Effect of Two Temperatures on Reflection Coefficient in Micropolar Thermoelastic with and without Energy Dissipation Media

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Rajneesh Kumar ◽  
K. D. Sharma ◽  
S. K. Garg
Keyword(s):  
Energy Dissipation ◽  
Temperature Effects ◽  
Plane Waves ◽  
Angle Of Incidence ◽  
Amplitude Ratios ◽  
Reflected Waves ◽  
Two Temperatures ◽  
Thermally Conducting ◽  
Without Energy Dissipation ◽  
Two Temperature

The reflection of plane waves at the free surface of thermally conducting micropolar elastic medium with two temperatures is studied. The theory of thermoelasticity with and without energy dissipation is used to investigate the problem. The expressions for amplitudes ratios of reflected waves at different angles of incident wave are obtained. Dissipation of energy and two-temperature effects on these amplitude ratios with angle of incidence are depicted graphically. Some special and particular cases are also deduced.

Wave propagation in an initially stressed rotating thermo-diffusive medium with two-temperature and micro-concentrations

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Devender Sheoran ◽  
Ramesh Kumar ◽  
Sunil Kumar ◽  
Kapil Kumar Kalkal
Keyword(s):  
Plane Waves ◽  
Generalized Thermoelasticity ◽  
Angle Of Incidence ◽  
Amplitude Ratios ◽  
Conservation Of Energy ◽  
Content Type ◽  
Reflected Waves ◽  
Diffusive Medium ◽  
Energy Ratios ◽  
Two Temperature

Purpose The purpose of this paper is to study the reflection of plane waves in an initially stressed rotating thermoelastic diffusive medium with micro-concentrations and two-temperature. Design/methodology/approach A two-dimensional model of generalized thermoelasticity is considered. The governing equations are transformed into the non-dimensional forms using the dimensionless variables. Then, potential functions are introduced for the decoupling of the waves. Further, appropriate boundary conditions are assumed to completely solve the problem. Finally, numerical computations are performed using MATLAB. Findings The problem is solved analytically and it is found that there exist five coupled waves in addition to an independent micro-concentration wave in the considered medium. The amplitude ratios and energy ratios of these reflected waves have also been computed numerically for a specific material. Originality/value The modulus values of amplitude ratios are presented graphically to exhibit the effects of angular velocity, initial stress, two-temperature, diffusion and micro-concentration parameters. The expressions of energy ratios obtained in explicit form are also depicted graphically as functions of angle of incidence. The law of conservation of energy at the free surface during reflection phenomenon is also verified.

scholarly journals Reflection at Free Surface in Micropolar Thermoelastic Solid with two Temperatures

2013 ◽  
Vol 18 (1) ◽  
pp. 217-234 ◽  
Author(s):  
K. Sharma
Keyword(s):  
Half Space ◽  
Plane Surface ◽  
Plane Waves ◽  
Relaxation Times ◽  
Specific Model ◽  
Angle Of Incidence ◽  
Amplitude Ratios ◽  
Two Temperatures ◽  
Generalized Thermoelastic ◽  
Thermoelastic Solid

The present investigation is concerned with the effect of two temperatures on reflection coefficients in a micropolar thermoelastic solid half space. With two relaxation times, reflection of plane waves impinging obliquely at a plane interface of the micropolar generalized thermoelastic solid half space with two temperatures is investigated. The incident wave is assumed to be striking at the plane surface after propagating through the micropolar generalized thermoelastic solid with two temperatures. Amplitude ratios of the various reflected waves are obtained in closed form and it is found that these are functions of angle of incidence, frequency and are affected by the elastic properties of the media. The effect of two temperatures is shown on these amplitude ratios for a specific model.

scholarly journals Reflection of Plane Waves from Surface of a Generalized Thermo-Viscoelastic Porous Solid Half-Space with Impedance Boundary Conditions

2020 ◽  
Vol 22 (4) ◽  
pp. 1483-1496
Author(s):  
Baljeet Singh
Keyword(s):  
Boundary Conditions ◽  
Half Space ◽  
Plane Waves ◽  
Angle Of Incidence ◽  
Amplitude Ratios ◽  
Impedance Boundary ◽  
Reflected Waves ◽  
Material Parameters ◽  
Impedance Boundary Conditions ◽  
Impedance Parameter

AbstractA phenomenon of reflection of plane waves from a thermally insulated surface of a solid half-space is studied in context of Lord-Shulman theory of generalized thermo-viscoelasticity with voids. The governing equations of generalized thermo-viscoelastic medium with voids are specialized in x–z plane. The plane wave solution of these equations shows the existence of three coupled longitudinal waves and a shear vertical wave in a generalized thermo-viscoelastic medium with voids. For incident plane wave (longitudinal or shear), three coupled longitudinal waves and a shear vertical wave reflect back in the medium. The mechanical boundary conditions at free surface of solid half-space are considered as impedance boundary conditions, in which the shear force tractions are assumed to vary linearly with the tangential displacement components multiplied by the frequency. The impedance corresponds to the constant of proportionality. The appropriate potentials of incident and reflected waves in the half-space will satisfy the required impedance boundary conditions. A non-homogeneous system of four equations in the amplitude ratios of reflected waves is obtained. These amplitude ratios are functions of material parameters, impedance parameter, angle of incidence, thermal relaxation and speeds of plane waves. Using relevant material parameters for medium, the amplitude ratios are computed numerically and plotted against certain ranges of impedance parameter and the angle of incidence.

scholarly journals Influence of Diffusion and Impedence Parameters on Wave Propagation in Thermoelastic Medium

2021 ◽  
Vol 26 (4) ◽  
pp. 99-112
Author(s):  
Sachin Kaushal ◽  
Rajneesh Kumar ◽  
Kulwinder Parmar
Keyword(s):  
Plane Waves ◽  
Angle Of Incidence ◽  
Amplitude Ratios ◽  
Thermoelastic Medium ◽  
Impedance Boundary ◽  
Reflected Waves ◽  
Diffusion Relaxation ◽  
Impedance Parameters ◽  
The Impact ◽  
Coupled Theory

Abstract The aim of the present paper is to study the impact of diffusion and impedance parameters on the propagation of plane waves in a thermoelastic medium for Green and Lindsay theory (G-L) and the Coupled theory (C-T) of thermoelasticity. Results are demonstrated for impedance boundary conditions and the amplitude ratios of various reflected waves against the angle of incidence are calculated numerically. The characteristics of diffusion, relaxation time and impedence parameter on amplitude ratios have been depicted graphically. Some cases of interest are also derived from the present investigation.

scholarly journals Propagation of plane waves in a rotating transversely isotropic two temperature generalized thermoelastic solid half-space with voids

2016 ◽  
Vol 21 (2) ◽  
pp. 285-301 ◽  
Author(s):  
R. Bijarnia ◽  
B. Singh
Keyword(s):  
Half Space ◽  
Plane Waves ◽  
Generalized Thermoelasticity ◽  
Transversely Isotropic ◽  
Reflection Coefficients ◽  
Angle Of Incidence ◽  
Reflected Waves ◽  
Generalized Thermoelastic ◽  
Thermoelastic Solid ◽  
Two Temperature

AbstractThe paper is concerned with the propagation of plane waves in a transversely isotropic two temperature generalized thermoelastic solid half-space with voids and rotation. The governing equations are modified in the context of Lord and Shulman theory of generalized thermoelasticity and solved to show the existence of four plane waves in thex – zplane. Reflection of these plane waves from thermally insulated stress free surface is also studied to obtain a system of four non-homogeneous equations. For numerical computations of speed and reflection coefficients, a particular material is modelled as transversely isotropic generalized thermoelastic solid half-space. The speeds of plane waves are computed against the angle of propagation to observe the effects of two temperature and rotation. Reflection coefficients of various reflected waves are also computed against the angle of incidence to observe the effects of various parameters.

scholarly journals Reflection and transmission of waves from imperfect boundary between two heat conducting micropolar thermoelastic solids

2014 ◽  
Vol 22 (2) ◽  
pp. 151-176 ◽  
Author(s):  
Kunal Sharma ◽  
Marin Marin
Keyword(s):  
Amplitude Ratio ◽  
Plane Waves ◽  
Elastic Solid ◽  
Heat Conducting ◽  
Angle Of Incidence ◽  
Reflection And Transmission ◽  
Transmission Coefficients ◽  
Transmitted Waves ◽  
Thermally Conducting ◽  
Two Temperature

AbstractThe problem of reflection and transmission of plane waves at an imperfect boundary between two thermally conducting micropolar elastic solid half spaces with two temperature is investigated. Amplitude ratio of various reflected and transmitted waves are presented when a set of coupled longitudinal wave (LD-wave) and thermal wave (T-wave) and a set of coupled transverse wave and microrotation waves (CDI, CDII) is made incident. The expressions for reflection and transmission coefficients which are the ratios of the amplitudes of reflected and transmitted waves at different angles of incident wave are obtained. The corresponding expressions for the normal force stiffness, transverse force stiffness, transverse couple stiffness and perfect bonding has also been included. Stiffness and two temperature e ects on these amplitude ratios with angle of incidence have been depicted graphically. Some special and particular cases are also discussed.

scholarly journals Reflection coefficients and energy ratios in a micropolar thermoelastic medium without energy dissipation

2007 ◽  
Vol 48 (3) ◽  
pp. 433-447 ◽  
Author(s):  
Baljeet Singh
Keyword(s):  
Energy Dissipation ◽  
Thermal Effects ◽  
Plane Waves ◽  
Reflection Coefficients ◽  
Angle Of Incidence ◽  
Dimensional Model ◽  
Governing Equations ◽  
Thermoelastic Medium ◽  
Energy Ratios ◽  
Without Energy Dissipation

AbstractThe linear governing equations of a micropolar thermoelastic medium without energy dissipation are solved to show the existence of four plane waves in a two-dimensional model. The expressions for velocities of these plane waves are obtained. The boundary conditions at the free surface are used to obtain a system of four nonhomogeneous equations. These equations are solved numerically for a particular model to obtain reflection coefficients for the incidence of coupled longitudinal displacement and coupled transverse microrotational waves. These reflection coefficients as well as the energy ratios are computed and are shown graphically with the angle of incidence in the presence and absence of thermal effects.

scholarly journals The Effect of a Hyperbolic Two-Temperature Model with and without Energy Dissipation in a Semiconductor Material

Mathematics ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 1711
Author(s):  
Faris Alzahrani ◽  
Ibrahim Abbas
Keyword(s):  
Energy Dissipation ◽  
Thermodynamic Temperature ◽  
Temperature Model ◽  
Conductive Temperature ◽  
Mechanical Waves ◽  
Without Energy Dissipation ◽  
Thermoelastic Waves ◽  
Analytical Expressions ◽  
Thermoelastic Theory ◽  
Two Temperature

In this work, the new model of photothermal and elastic waves, with and without energy dissipation, under a hyperbolic two-temperature model, is used to compute the displacement, carrier density, thermodynamic temperature, conductive temperature and stress in a semiconductor medium. The medium is considered in the presence of the coupling of plasma and thermoelastic waves. To get the complete analytical expressions of the main physical fields, Laplace transforms and the eigenvalue scheme are used. The outcomes are presented graphically to display the differences between the classical two-temperature theory and the new hyperbolic two-temperature theory, with and without energy dissipation. Based on the numerical results, the hyperbolic two-temperature thermoelastic theory offers a finite speed of mechanical waves and propagation of thermal waves.

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