Memory-dependent derivatives for photothermal semiconducting medium in generalized thermoelasticity with two-temperature
20 Feb 2017-Mechanics of Time-dependent Materials (Springer Netherlands)-Vol. 21, Iss: 4, pp 519-534
TL;DR: In this article, a generalized model of photothermal theory with two-temperature thermoelasticity theory based on memory-dependent derivative (MDD) theory is performed for a one-dimensional problem for an elastic semiconductor material with isotropic and homogeneous properties.
Abstract: In this work, a novel generalized model of photothermal theory with two-temperature thermoelasticity theory based on memory-dependent derivative (MDD) theory is performed. A one-dimensional problem for an elastic semiconductor material with isotropic and homogeneous properties has been considered. The problem is solved with a new model (MDD) under the influence of a mechanical force with a photothermal excitation. The Laplace transform technique is used to remove the time-dependent terms in the governing equations. Moreover, the general solutions of some physical fields are obtained. The surface taken into consideration is free of traction and subjected to a time-dependent thermal shock. The numerical Laplace inversion is used to obtain the numerical results of the physical quantities of the problem. Finally, the obtained results are presented and discussed graphically.
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TL;DR: In this article, a mathematical model under the effect of Thomson heating of a semi-infinite semiconductor elastic medium is expressed and the charge density of induced electric current is expressed for a time functionally only.
Abstract: In this article, the novel mathematical model under the effect of Thomson heating of a semi-infinite semiconductor elastic medium is expressed. The thermoelasticity theory is applied in the presence of magnetic field when the medium illuminated by a laser pulse in context of photothermal excitation. The discussions are focused on studying the overlapping between plasma, thermal, electro-magnetic and elastic waves when they propagated in the medium. The two dimensional (2D) deformations is used in the governing equations when the medium is homogenous and isotropic. The charge density of induced electric current is expressed for a time functionally only. The physical fields are obtained when use the normal mode technique with some thermal, mechanical and plasma loads occur at the free surface of elastic semi-infinite semiconductor medium. The numerical calculations of physical field's distributions are discussed and shown graphically under the effect of Thomson parameter.
78 citations
TL;DR: In this paper, a model of fractional order heat conduction law for a spherical cavity of a semiconductor medium with a photothermal process has been proposed, where the inner surface of the cavity is taken traction free with thermal shock.
Abstract: In this paper, we consider a one dimensional problem of waves in a thermoelastic infinite medium with a spherical cavity. We are concerned with the study a new model of fractional order heat conduction law for a spherical cavity of a semiconductor medium. The governing equations are solved under the effect of the theory of coupled plasma, elastic, thermal waves through a photothermal process. The inner surface of the cavity is taken traction free with thermal shock. Time-dependence is removed by Laplace transform technique to governing equations. This method has been used to get the exact expression of some physical quantities, thermal activation coupling parameters and illustrated graphically.
57 citations
TL;DR: In this article, a generalized generalized thermoelasticity theory and coupled plasma theory for a semi-infinite semiconductor elastic medium were studied in context of the Photothermal transport process for isoropic homogenous two-dimensional medium.
Abstract: The aim of this investigation is to study a refined multi-phase-lags generalized thermoelasticity theory and coupled plasma theory for a semi-infinite semiconductor elastic medium. The model is studied in context of the Photothermal transport process for isoropic homogenous two dimension medium. The governing equations describe the interaction between elastic-plasma-thermal waves. The normal mode technique is used to get the exact solutions analytically of main physical quantities under investigation. The thermal-plasma and mechanical loads are applied at the free surface of semiconductor medium to obtain the complete solution of the temperature, displacement, stresses and carrier density distributions. Some special cases have been obtained. Results will be displayed graphically and discussed. Comparisons are made between the different theories in thermoelasticity.
55 citations
TL;DR: In this article, a mathematical model for the piezoelectric elastic-semiconductor medium is developed, where the medium is homogeneous and isotropic that is exposed to photothermal excitation.
Abstract: The main goal of this paper is to develop a mathematical model for the piezoelectric elastic-semiconductor medium. The medium is homogeneous and isotropic that is exposed to photothermal excitation...
54 citations
TL;DR: In this article, a novel mathematical model of magneto-thermoelasticity was proposed to investigate the transient phenomena for a fiber-reinforced thick plate having a heat source.
Abstract: Enlightened by the Caputo fractional derivative, the present study deals with a novel mathematical model of magneto-thermoelasticity to investigate the transient phenomena for a fibre-reinforced thick plate having a heat source in the context of three-phase-lag model of generalized thermoelasticity, which is defined in an integral form of a common derivative on a slipping interval by incorporating the memory-dependent heat transfer. The upper surface of the plate is free of traction having a prescribed surface temperature while the lower surface rests in a rigid foundation and is thermally insulated. Employing Laplace and Fourier transforms as tools, the problem has been solved analytically in the transformed domain. The inversion of the Fourier transform is carried out using suitable numerical techniques while the numerical inversion of Laplace transform is done incorporating a method on Fourier series expansion technique. According to the graphical representations corresponding to the numerical results, conclusions about the new theory is constructed. Excellent predictive capability is demonstrated due to the presence of memory dependent derivative, magnetic field and reinforcement also.
53 citations
References
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TL;DR: In this paper, a linear dissipative mechanism whose Q is almost frequency independent over large frequency ranges has been investigated by introducing fractional derivatives in the stressstrain relation, and a rigorous proof of the formulae to be used in obtaining the analytic expression of Q is given.
Abstract: Summary Laboratory experiments and field observations indicate that the Q of many non-ferromagnetic inorganic solids is almost frequency independent in the range 10-2-107 cis, although no single substance has been investigated over the entire frequency spectrum. One of the purposes of this investigation is to find the analytic expression for a linear dissipative mechanism whose Q is almost frequency independent over large frequency ranges. This will be obtained by introducing fractional derivatives in the stressstrain relation. Since the aim of this research is also to contribute to elucidating the dissipating mechanism in the Earth free modes, we shall treat the dissipation in the free, purely torsional, modes of a shell. The dissipation in a plane wave will also be treated. The theory is checked with the new values determined for the Q of spheroidal free modes of the Earth in the range between 10 and 5 min integrated with the Q of Rayleigh waves in the range between 5 and 0.6 min. Another check of the theory is made with the experimental values of the Q of the longitudinal waves in an aluminium rod in the range between lo-’ and 10-3s. In both checks the theory represents the observed phenomena very satisfactorily. The time derivative which enters the stress-strain relation in both cases is of order 0.15. The present paper is a generalized version of another (Caputo 1966b) in which an elementary definition of some differential operators was used. In this paper we give also a rigorous proof of the formulae to be used in obtaining the analytic expression of Q; moreover, we present two checks of the theory with experimental data. The present paper is a generalized version of another (Caputo 1966b) in which an elementary definition of some differential operators was used. In this paper we give also a rigorous proof of the formulae to be used in obtaining the analytic expression of Q; moreover, we present two checks of the theory with experimental data. In a homogeneous isotropic elastic field the elastic properties of the substance are specified by a description of the strains and stresses in a limited portion of the field since the strains and stresses are linearly related by two parameters which describe the elastic properties of the field. If the elastic field is not homogeneous nor isotropic the properties of the field are specified in a similar manner by a larger number of parameters which also depend on the position.
3,372 citations
TL;DR: In this article, a generalized dynamical theory of thermoelasticity is formulated using a form of the heat transport equation which includes the time needed for acceleration of heat flow.
Abstract: In this work a generalized dynamical theory of thermoelasticity is formulated using a form of the heat transport equation which includes the time needed for acceleration of the heat flow. The theory takes into account the coupling effect between temperature and strain rate, but the resulting coupled equations are both hyperbolic. Thus, the paradox of an infinite velocity of propagation, inherent in the existing coupled theory of thermoelasticity, is eliminated. A solution is obtained using the generalized theory which compares favourably with a known solution obtained using the conventional coupled theory.
3,266 citations
TL;DR: In this article, a unified treatment of thermoelasticity by application and further developments of the methods of irreversible thermodynamics is presented, along with a new definition of the dissipation function in terms of the time derivative of an entropy displacement.
Abstract: A unified treatment is presented of thermoelasticity by application and further developments of the methods of irreversible thermodynamics. The concept of generalized free energy introduced in a previous publication plays the role of a ``thermoelastic potential'' and is used along with a new definition of the dissipation function in terms of the time derivative of an entropy displacement. The general laws of thermoelasticity are formulated in a variational form along with a minimum entropy production principle. This leads to equations of the Lagrangian type, and the concept of thermal force is introduced by means of a virtual work definition. Heat conduction problems can then be formulated by the methods of matrix algebra and mechanics. This also leads to the very general property that the entropy density obeys a diffusion‐type law. General solutions of the equations of thermoelasticity are also given using the Papkovitch‐Boussinesq potentials. Examples are presented and it is shown how the generalized coordinate method may be used to calculate the thermoelastic internal damping of elastic bodies.
2,287 citations
Book•
02 Dec 2010
TL;DR: In this paper, the existence and uniqueness results for Riemann-Liouville Fractional Differential Equations are presented. But they do not cover the special cases of fractional calculus.
Abstract: Fundamentals of Fractional Calculus.- Riemann-Liouville Differential and Integral Operators.- Caputo's Approach.- Mittag-Leffler Functions.- Theory of Fractional Differential Equations.- Existence and Uniqueness Results for Riemann-Liouville Fractional Differential Equations.- Single-Term Caputo Fractional Differential Equations: Basic Theory and Fundamental Results.- Single-Term Caputo Fractional Differential Equations: Advanced Results for Special Cases.- Multi-Term Caputo Fractional Differential Equations.
2,263 citations
IBM1
TL;DR: In this article, the theory and applications of photo-acoustic (also called optoacoustic) methods belonging to the more general area of photothermal measurement techniques are reviewed, covering excitation of gaseous or condensed samples with modulated continuous light beams or pulsed light beams.
Abstract: This paper reviews the theory and applications of photoacoustic (also called optoacoustic) methods belonging to the more general area of photothermal measurement techniques. The theory covers excitation of gaseous or condensed samples with modulated continuous light beams or pulsed light beams. The applications of photoacoustic methods include spectroscopy, monitoring deexcitation processes, probing physical properties of materials, and generating mechanical motions. Several other related photothermal methods, as well as particle-acoustics and wave-acoustics methods are also described. This review complements an earlier and narrower review [Rev. Mod. Phys. 53, 517 (1981)] that is mainly concerned with sensitive detection by pulsed photoacoustic spectroscopy in condensed matter.
1,183 citations