• Steel and Composite Structures
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• v.36 no.3
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• pp.249-259
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• 2020

In this work, a novel three-dimensional model in the generalized thermoelasticity for a homogeneous an isotropic medium was investigated with diffusion, under the effect of thermal loading due to laser pulse in the context of Green-Lindsay theory was investigated. The normal mode analysis technique is used to solve the resulting non-dimensional equations of the problem. Numerical results for the displacement, the thermal stress, the strain, the temperature, the mass concentration, and the chemical potential distributions are represented graphically to display the effect of the thermal loading due to laser pulse and the relaxation time on the resulting quantities. Comparisons are made within the theory in the presence and absence of laser pulse.

• Steel and Composite Structures
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• v.38 no.5
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• pp.523-531
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• 2021

The generalized thermoelastic analysis problem of a two-dimension porous medium with and without energy dissipation are obtained in the context of Green-Naghdi's (GNIII) model. The exact solutions are presented to obtain the studying fields due to the pulse heat flux that decay exponentially in the surface of porous media. By using Laplace and Fourier transform with the eigenvalues scheme, the physical quantities are analytically presented. The surface is shocked by thermal (pulse heat flux problems) and applying the traction free on its outer surfaces (mechanical boundary) through transport (diffusion) process of temperature to observe the analytical complete expression of the main physical fields. The change in volume fraction field, the variations of the displacement components, temperature and the components of stress are graphically presented. Suitable discussion and conclusions are presented.

• Structural Engineering and Mechanics
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• v.72 no.4
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• pp.455-468
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• 2019

The present article is aimed at studying the reflection phenomena of plane waves in a homogeneous, orthotropic, initially stressed magneto-thermoelastic rotating medium with diffusion. The enuciation is applied to generalized thermoelasticity based on Lord-Shulman theory. There exist four coupled waves, namely, quasi-longitudinal P-wave (qP), quasi-longitudinal thermal wave (qT), quasi-longitudinal mass diffusive wave (qMD) and quasi-transverse wave (qSV) in the medium. The amplitude and energy ratios for these reflected waves are derived and the numerical computations have been carried out with the help of MATLAB programming. The effects of rotation, initial stress, magnetic and diffusion parameters on the amplitude ratios are depicted graphically. 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 also depicted on velocities of various reflected waves.

• Structural Engineering and Mechanics
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• v.73 no.6
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• pp.725-735
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• 2020

The present investigation deals with the thermomechanical interactions in an orthotropic thermoelastic homogeneous body in the context of fractional order theory of thermoelasticity due to time harmonic sources. The application of a time harmonic concentrated and distributed sources has been considered to show the utility of the solution obtained. Assuming the disturbances to be harmonically time dependent, the expressions for displacement components, stress components and temperature change are derived in frequency domain. Numerical inversion technique has been used to determine the results in physical domain. The effect of frequency on various components has been depicted through graphs.

• Structural Engineering and Mechanics
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• v.4 no.2
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• pp.191-202
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• 1996

This paper presents a construction of adaptive boundary element for the problem with mixed boundary conditions such as heat transfer between heated body surface and surrounding medium. The scheme is based on the sample point error analysis and on the extended error indicator, proposed earlier by the authors for the potential and elastostatic problems, and extended successfully to multidomain and thermoelastic analyses. Since the field variable is connected with its derivative on the boundary, their errors are also interconnected by the specified condition. The extended error indicator on each boundary element is modified to meet with the situation. Two numerical examples are shown to indicate the differences due to the prescribed boundary conditions.

• Structural Engineering and Mechanics
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• v.30 no.5
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• pp.577-592
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• 2008

Laplace-Fourier transform techniques are used to investigate the interaction caused by mechanical, thermal and microstress sources in a generalized thermomicrostretch elastic medium with temperature-dependent mechanical properties. The modulus of elasticity is taken as a linear function of reference temperature. The integral transforms are inverted using a numerical technique to obtain the normal stress, tangential stress, tangential couple stress, microstress and temperature distribution. Effect of temperature dependent modulus of elasticity and thermal relaxation times have been depicted graphically on the resulting quantities. Comparisons are made with the results predicted by the theories of generalized thermoelasticity. Some particular cases are also deduced from the present investigation.

• Coupled systems mechanics
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• v.10 no.1
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• pp.21-38
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• 2021

This work is an attempt to design a dynamic model for a non local bio-thermoelastic medium with diffusion. The system of governing equations are formulated in terms of displacement vector field, chemical potential and the tissue temperature in the context of non local dual phase lag (NL DPL) theories of heat conduction and mass diffusion. Based on this considered model, we study the fundamental solution and propagation of plane harmonic waves in tissues. In order to analyze the behavior of the NL DPL model, we construct basic theorem in the terms of elementary function which determine the existence of three longitudinal and one transverse wave. The effects of various parameters on the characteristics of waves i.e., phase velocity and attenuation coefficients are elaborated by plotting various figures of physical quantities in the later part of the paper.

• Coupled systems mechanics
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• v.13 no.1
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• pp.21-41
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• 2024

This paper is concerned with the disturbances in a transversely isotropic new modified couple stress homogeneous thermoelastic rotating medium under the combined influence of Hall currents, magnetic fields, and mechanical sources represented by inclined loads. The application of Laplace and Fourier transform techniques are used for the derivation of analytical expressions for various physical quantities. As an application,the bounding surface is subjected to uniformly and linearly distributed force (mechanical force). Present model contains length scale parameters that can capture the size effects. Numerical inversion techniques has been used to provide insights into the system's behavior in the physical domain. The graphical representation of numerical simulated results has been presented to emphasize the impact of rotation and inclined line loads on the system, enhancing our understanding of the studied phenomena. Further research can extend this study to investigate additional complexities and real-world applications.

• Steel and Composite Structures
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• v.22 no.3
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• pp.567-587
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• 2016

The present investigation is to study the plane wave propagation and reflection of plane waves in a homogeneous transversely isotropic magnetothermoelastic medium with two temperature and rotation in the context of GN Type-II and Type-III (1993) theory of thermoelasticity. It is found that, for two dimensional assumed model, there exist three types of coupled longitudinal waves, namely quasi-longitudinal wave (QL), quasi-transverse wave (QTS) and quasi-thermal waves (QT). The different characteristics of waves like phase velocity, attenuation coefficients, specific loss and penetration depth are computed numerically and depicted graphically. The phenomenon of reflection coefficients due to quasi-waves at a plane stress free with thermally insulated boundary is investigated. The ratios of the linear algebraic equations. These amplitude ratios are used further to calculate the shares of different scattered waves in the energy of incident wave. The modulus of the amplitude and energy ratios with the angle of incidence are computed for a particular numerical model. The conservation of energy at the free surface is verified. The effect of energy dissipation and two temperatures on the energy ratios are depicted graphically and discussed. Some special cases of interest are also discussed.