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1

Effect of thermal loading due to laser pulse on 3-d problem of micropolar thermoelastic solid with energy dissipation

Othman M. I. A., Atwa S. Y., Elwan A. W.

Mechanics and Mechanical Engineering

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2017

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Vol. 21, nr 3

679--701

EN

The aim of this paper is to introduce the Green-Naghdi (G-N) theory of type III (with energy dissipation) to study the effect of thermal loading due to laser pulse on generalized micropolar thermoelastic homogeneous isotropic medium in three dimensions. The normal mode analysis technique is used to solve the resulting non-dimensional equations of the problem. Numerical results for the displacement, thermal stress, strain, temperature, couple stresses and micro-rotation distributions are represented graphically to display the effect of the laser pulse on the resulting quantities. Comparisons are made within the theory in the presence and absence of the laser pulse.

2

The effect of rotation and thermal shock on a perfect conducting elastic half-space in generalized magneto-thermoelasticity with two relaxation times

Othman M. I. A.

Mechanics and Mechanical Engineering

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2010

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Vol. 14, nr 1

31-55

EN

The propagation of electromagneto-thermoelastic disturbances produced by a thermal shock in a perfectly conducting elastic half-space when the entire elastic medium is rotating with a uniform angular velocity is investigated. The problem is in the context of the Green and Lindsay's generalized thermoelasticity with two relaxation times. There acts an initial magnetic field parallel to the plane boundary of the half-space. The medium deformed because of thermal shock, and due to the application of the magnetic field. The normal mode analysis is used to obtain the exact expressions for the considered variables. The distributions of the considered variables are represented graphically. From the distributions, it can be found the wave type heat propagation in the medium. This indicates that the generalized heat conduction mechanism is completely different from the classic Fourier's in essence. In generalized thermoelasticity theory heat propagates as a wave with finite velocity instead of infinite velocity in medium. Comparisons are made wit h the results predicted by the coupled theory in present and absent rotation.

3

Deformation in a Generalized Thermoelastic Medium with Hydrostatic Initial Stress Subjected to Different Sources

Ailawalia P., Kumar S., Khurana G.

Mechanics and Mechanical Engineering

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2009

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Vol. 13, nr 1

5-24

EN

In the present problem we study the deformation of a rotating generalized thermoelastic medium with hydrostatic initial stress subjected to three different type of sources. The components of displacement, force stress and temperature distribution are obtained in Laplace and Fourier domain by applying integral transforms. The general solution obtained is applied to a specific problem of a half-space subjected to concentrated force, distributed force and a moving source. These components are then obtained in the physical domain by applying a numerical inversion method. Some particular cases are also discussed in context of the problem. The results are also presented graphically to show the effect of rotation and hydrostatic initial stress.

4

Generalized Thermoelasticity Plane Waves in Rotating Media with Thermal Relaxation under the Temperature Dependent Properties

Othman M. I. A.

Mechanics and Mechanical Engineering

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2005

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Vol. 9, nr 2

89--110

EN

A two-dimensional coupled problem in generalized thermoelasticity for rotating media under the temperature dependent properties is studied. The problem is in the context of the Lord-Shulman's theory with one relaxation time. The normal mode analysis is used to obtain the expressions for the temperature distribution, displacement components and thermal stresses. The resulting formulation is applied to two different problems. The first concerns the case of a heat punch moving across the surface of a semi-infinite thermoelastic half-space subjected to appropriate boundary conditions. The second deals with a thick plate subject to a time-dependent heat source on each face. Numerical results are illustrated graphically for each problem considered. Comparisons are made with the results obtained predicted by the two theories in case of absence of rotation.

5

Elastodynamic response of Mechanical and Thermal sources in Generalized Thermoelastic Half-space with Voids

Kumar R., Rani L.

Mechanics and Mechanical Engineering

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2005

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Vol. 9, nr 2

29--45

EN

The dynamic response of a homogeneous, isotropic, generalized thermoelastic half-space with voids subjected to normal, tangential force and thermal source is investigated. The displacements, stresses, temperature distribution and change in volume fraction field so obtained in the physical domain are computed numerically and illustrated graphically. The numerical results of these quantities for magnesium crystal-like material are illustrated to depict voids effect in the Lord-Shulman (L-S) theory and Green-Lindsay (G-L) theory for an insulated boundary and temperature gradient boundary.

6

Maysel's formula in the generalized linear micropolar thermoviscoelasticity

El-Karamany A. S.

Archives of Mechanics

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2004

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Vol. 56, nr 5

357-376

EN

Generalizations of Maysel's formula to generalized linear micropolar thermoviscoelasticity is given. Fundamental solutions in the Laplace transform domain are obtained. The results are applicable to the following generalized thermoelasticity theories: Lord-Shulman theory with one relaxation time, Green-Lindsay theory with two relaxation times, Green-Naghdi theory of type III, and the Chandrasekharaiah and Tzou theory with dual-phase lag, as well as to the dynamic coupled theory. The cases of generalized linear micropolar thermoviscoelasticity of the Kelvin-Voigt model, and the generalized linear micropolar thermoelasticity can be obtained from the given results.