Mohamed Abdelsabour Fahmy^1,2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.1, pp. 175-199, 2021, DOI:10.32604/cmes.2021.012218 - 22 December 2020

Abstract The main aim of this paper is to propose a new memory dependent derivative (MDD) theory which called threetemperature nonlinear generalized anisotropic micropolar-thermoelasticity. The system of governing equations of the problems associated with the proposed theory is extremely difficult or impossible to solve analytically due to nonlinearity, MDD diffusion, multi-variable nature, multi-stage processing and anisotropic properties of the considered material. Therefore, we propose a novel boundary element method (BEM) formulation for modeling and simulation of such system. The computational performance of the proposed technique has been investigated. The numerical results illustrate the effects of time More >

Mahmoud A. Ismail^a, Shadia Fathi Mohamed El Sherif ^a , A. A. El-Bary^b,*, Hamdy M. Youssef^c

Frontiers in Heat and Mass Transfer, Vol.14, pp. 1-7, 2020, DOI:10.5098/hmt.14.3

Abstract In this paper we will discuss the problem of distribution of thermal stresses and temperature in a generalized magneto–thermo-viscoelastic solid spherical cavity of radius R according to Green- Naghdi (G-N II) and (G-N III) theory. The surface of the cavity is assumed to be free traction and subjected to a constant thermal shock. The Laplace transform technique is used to solve the problem. The state space approach is adopted for the solution of one dimensional problem. Solution of the problem in the physical domain are obtained by using a numerical method of MATLAP Programmer and More >

Fatima Bayones¹, Abdelmooty Abd-Alla^{2, *}, Raghad Alfatta³, Hoda Al-Nefaie³

CMC-Computers, Materials & Continua, Vol.62, No.2, pp. 551-567, 2020, DOI:10.32604/cmc.2020.08420

Abstract The propagation of thermoelastic waves in a homogeneous, isotropic elastic semi-infinite space is subjected to rotation and initial stress, which is at temperature T₀ - initially, and whose boundary surface is subjected to heat source and load moving with finite velocity. Temperature and stress distribution occurring due to heating or cooling and have been determined using certain boundary conditions. Numerical results have been given and illustrated graphically in each case considered. Comparison is made with the results predicted by the theory of thermoelasticity in the absence of rotation and initial stress. The results indicate that the More >

Najat A. Alghamdi¹, Hamdy M. Youssef^2,3,*

FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.5, pp. 597-611, 2019, DOI:10.32604/fdmp.2019.05131

Abstract A mathematical model is elaborated for a thermoelastic infinite body with a spherical cavity. A generalized set of governing equations is formulated in the context of three different models of thermoelasticity: the Biot model, also known as “coupled thermoelasticity” model; the Lord-Shulman model, also referred to as “generalized thermoelasticity with one-relaxation time” approach; and the Green-Lindsay model, also called “generalized thermoelasticity with two-relaxation times” approach. The Adomian’s decomposition method is used to solve the related mathematical problem. The bounding plane of the cavity is subjected to harmonic thermal loading with zero heat flux and strain. More >

A. M. Abd-Alla^1,2,3, Mohamed I. A. Othman^1,4, S. M. Abo-Dahab^1,5

CMC-Computers, Materials & Continua, Vol.51, No.2, pp. 63-79, 2016, DOI:10.3970/cmc.2016.051.063

Abstract The aim of this paper is to study the reflection of plane harmonic waves from a semi-infinite elastic solid under the effect of magnetic field in a vacuum. The expressions for the reflection coefficients, which are the relations of the amplitudes of the reflected waves to the amplitude of the incident waves, are obtained. Similarly, the reflection coefficient ratio variations with the angle of incident under different conditions are shown graphically. Comparisons are made with the results predicted by the dual-phase-lag model and Lord-Shulman theory in the presence and absence of magnetic field. More >

Jan Sladek¹, Vladimir Sladek¹, Peter Stanak¹

CMES-Computer Modeling in Engineering & Sciences, Vol.106, No.4, pp. 229-262, 2015, DOI:10.3970/cmes.2015.106.229

Abstract The scaled boundary finite element method (SBFEM) is presented to study thermoelastic problems in materials with voids. The SBFEM combines the main advantages of the finite element method (FEM) and the boundary element method (BEM). In this method, only the boundary is discretized with elements leading to a reduction of spatial dimension by one. It reduces computational efforts in mesh generation and CPU. In contrast to the BEM, no fundamental solution is required, which permits to analyze general boundary value problems, where the conventional BEM cannot be applied due to missing fundamental solution. The computational More >

Tianhu He^1,2,3, Yongbin Ma^2,3, Shuanhu Shi³

CMC-Computers, Materials & Continua, Vol.47, No.1, pp. 15-29, 2015, DOI:10.3970/cmc.2015.047.015

Abstract The dynamic response of a two-dimensional generalized thermoelastic problem with temperature-dependent properties is investigated in the context of generalized thermoelasticity proposed by Lord and Shulman. The governing equations are formulated, and due to the nonlinearity and complexity of the governing equations resulted from the temperature-dependent properties, a numerical method, i.e., finite element method is adopted to solve such problem. By means of virtual displacement principle, the nonlinear finite element equations are derived. To demonstrate the solution process, a thermoelastic half-space subjected to a thermal shock on its bounding surface is considered in detail. The nonlinear… More >

Mohamed I. A. Othman^1,2,3, W. M. Hasona^2,4, Nehal T. Mansour^2,5

CMC-Computers, Materials & Continua, Vol.45, No.3, pp. 203-220, 2015, DOI:10.3970/cmc.2015.045.203

Abstract The problem of the generalized thermoelastic medium for three different theories under the effect of a gravitational field is investigated. The Lord- Shulman, Green-Naghdi III, three-phase-lag theories are discussed with twotemperature. The normal mode analysis is used to obtain the analytical expressions of the displacement components, force stress, thermodynamic temperature and conductive temperature. The numerical results are given and presented graphically, when the thermal force is applied. Comparisons are made with the results predicted by three-phase-lag model, Green-Naghdi III and Lord-Shulman theories in the presence and absence of gravity as well as two temperature. More >

Mohamed I. A. Othman¹, Magda E. M. Zidan¹, Mohamed I. M. Hilal¹

CMC-Computers, Materials & Continua, Vol.40, No.3, pp. 179-201, 2014, DOI:10.3970/cmc.2014.040.179

Abstract This investigation is aimed to study the two dimensional problem of thermoelastic medium with voids under the effect of the gravity. The modulus of elasticity is taken as a linear function of the reference temperature and employing the two-temperature generalized thermoelasticity. The problem is studied in the context of Green-Naghdi (G-N) theory of types II and III. The normal mode analysis method is used to obtain the exact expressions for the physical quantities which have been shown graphically by comparison between two types of the (G-N) theory in the presence and the absence of the More >

Y.C. Shiah¹, C.L. Tan^2,3

CMES-Computer Modeling in Engineering & Sciences, Vol.102, No.6, pp. 425-447, 2014, DOI:10.3970/cmes.2014.102.425

Abstract Green’s functions, or fundamental solutions, are necessary items in the formulation of the boundary integral equation (BIE), the analytical basis of the boundary element method (BEM). In the formulation of the BEM for 3D general anisotropic elasticity, considerable attention has been devoted to developing efficient algorithms for computing these quantities over the years. The mathematical complexity of this Green’s function has also posed an obstacle in the development of this numerical method to treat problems of 3D anisotropic thermoelasticity. This is because thermal effects manifest themselves as an additional domain integral in the integral equation;… More >