Time filter

Source Type

Kumara R.,Kurukshetra University | Guptab V.,Indira Gandhi National College
Journal of Engineering Physics and Thermophysics | Year: 2015

A dual-phase-lag diffusion model, augmenting the Fick law by the inclusion of the delay times of the mass flow and the potential gradient at the interface between two media into it, is proposed. The effects of reflection and refraction of plane waves at the interface between an elastic and a thermoelastic diffusion media were investigated with the use of this model. It was established that the ratios between the amplitudes and energies of the waves reflected and refracted at the interface between the indicated media are determined by the angle of incidence of radiation on this interface, the frequency of the incident wave, and the thermoelastic and diffusion properties of the media. Expressions for the ratios between the energies of different reflected and refracted waves and the energy of the incident were derived. The variation in these ratios with change in the angle of incidence of radiation on the indicated interface was calculated numerically and represented graphically. ©2015 Springer Science+Business Media New York.


Kumar R.,Kurukshetra University | Gupta V.,Indira Gandhi National College
Journal of Solid Mechanics | Year: 2015

The present investigation deals with the reflection and transmission phenomenon due to incident plane longitudinal wave at a plane interface between inviscid fluid half-space and a thermoelastic diffusion solid half-space with dual-phase-lag heat transfer (DPLT) and dual-phase-lag diffusion (DPLD) models. The theory of thermoelasticity with dual-phase-lag heat transfer developed by Roychoudhary [10] has been employed to develop the equation for thermoelastic diffusion with dual-phase-lag heat transfer and dual-phase-lag diffusion model. Amplitude ratios and energy ratios of various reflected and transmitted waves are obtained. It is found that these are the functions of angle of incidence, frequency of incident wave and are influenced by thermoelastic diffusion properties of media. The nature of dependence of amplitude ratios and energy ratios with the angle of incidence have been computed numerically for a particular model. The variations of energy ratios with angle of incidence are also shown graphically. The conservation of energy at the interface is verified. Some special cases are also deduced from the present investigation. © 2015 IAU, Arak Branch.


Kumar R.,Kurukshetra University | Gupta V.,Indira Gandhi National College
Canadian Journal of Physics | Year: 2015

This paper is concerned with the study of propagation of Rayleigh waves in a homogeneous isotropic generalized thermoelastic solid half space with mass diffusion in the context of the Lord-Shulman (Lord and Shulman. J. Mech. Phys. Solids. 15, 299 (1967)) and Green-Lindsay (Green and Lindsay. J. Elasticity. 2, 1 (1972)) theories of thermoelasticity. The medium is subjected to stress-free, isothermal, isoconcentrated boundary. After developing a mathematical model, the dispersion curve in the form of a polynomial equation is obtained. The roots of this polynomial equation are verified for not satisfying the original dispersion equation and therefore are filtered out and the remaining roots are checked with the property of decay with depth. Phase velocity and attenuation coefficient of the Rayleigh wave are computed numerically. The numerically simulated results are depicted graphically. The behavior of the particle motion is studied for the propagation of Rayleigh waves under Lord-Shulman model. Some special cases are also deduced from the present investigation. © 2015 Published by NRC Research Press.


Kumar R.,Kurukshetra University | Gupta V.,Indira Gandhi National College
Multidiscipline Modeling in Materials and Structures | Year: 2015

Purpose - The purpose of this paper is to study the propagation of Rayleigh waves in thermoelastic medium with mass diffusion. Design/methodology/approach - The field equations for the linear theory of homogeneous isotropic thermoelastic diffusion medium are taken into consideration by using dual-phase-lag heat transfer (DPLT) and dual-phase-lag diffusion (DPLD) models. Using the potential functions and harmonic wave solution, three coupled dilatational waves and a shear wave is obtained. After developing mathematical formulation, the dispersion equation is obtained, which results to be complex and irrational. This equation is converted into a polynomial form of higher degree. Findings - From the polynomial equation, Rayleigh wave root is found. The secular equation is resolved into a polynomial form to find the roots and therefore to find the existence and propagation of Rayleigh wave. The existence of Rayleigh wave in the assumed model depends on the values of various parameters involved in the secular equation. These roots are resolved for phase velocity and attenuation of the inhomogeneous propagation of Rayleigh wave. Behavior of particle motion of these waves inside and at the surface of the thermoelastic medium with mass diffusion is studied. Particular cases of the interest are also deduced from the present investigation. Originality/value - Governing equations corresponding to DPLT and DPLD models of thermoelastic diffusion are formulated to study the wave propagation and their dependence on various material parameters. In this paper effects of thermal and diffusion phase lags on the phase velocity, attenuation and on particle paths are observed and depicted graphically. © Emerald Group Publishing Limited.


Kumar R.,Kurukshetra University | Gupta V.,Indira Gandhi National College
Journal of Thermal Stresses | Year: 2014

The aim of the present article is to study the Green's function in transversely isotropic thermoelastic diffusion bimaterial. With this objective, first the three-dimensional general solution in transversely isotropic thermoelastic diffusion bimaterial is derived. On the basis of general solution, Green's function, with a concentrated heat source in steady state, is completely solved using harmonic functions. The components of displacement, stress, temperature distribution, and mass concentration are expressed in terms of elementary functions. The resulting quantities are computed numerically and illustrated graphically. A particular case of three-dimensional Green function in transversely isotropic thermoelastic bimaterial has been deduced from the present investigation. © Taylor & Francis Group, LLC.


Kumar R.,Kurukshetra University | Gupta V.,Indira Gandhi National College
Multidiscipline Modeling in Materials and Structures | Year: 2014

Purpose - The purpose of this paper is to depict the effect of thermal and diffusion phase-lags on plane waves propagating in thermoelastic diffusion medium with different material symmetry. A generalized form of mass diffusion equation is introduced instead of classical Fick's diffusion theory by using two diffusion phase-lags, one phase-lag of diffusing mass flux vector, represents the delayed time required for the diffusion of the mass flux and the other phase-lag of chemical potential, represents the delayed time required for the establishment of the potential gradient. The basic equations for the anisotropic thermoelastic diffusion medium in the context of dual-phase-lag heat transfer (DPLT) and dual-phase-lag diffusion (DPLD) models are presented. The governing equations for transversely isotropic and isotropic case are also reduced. The different characteristics of waves like phase velocity, attenuation coefficient, specific loss and penetration depth are computed numerically. Numerically computed results are depicted graphically for anisotropic, transversely isotropic and isotropic medium. The effect of diffusion and thermal phase-lags are shown on the different characteristic of waves. Some particular cases of result are also deduced from the present investigation.Design/methodology/approach - The governing equations of thermoelastic diffusion are presented using DPLT model and a new model of DPLD. Effect of phase-lags of thermal and diffusion is presented on different characteristic of waves.Findings - The effect of diffusion and thermal phase-lags on the different characteristic of waves is appreciable. Also the use of diffusion phase-lags in the equation of mass diffusion gives a more realistic model of thermoelastic diffusion media as it allows a delayed response between the relative mass flux vector and the potential gradient.Originality/value - Introduction of a new model of DPLD in the equation of mass diffusion. © Emerald Group Publishing Limited.

Loading Indira Gandhi National College collaborators
Loading Indira Gandhi National College collaborators