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This article discusses changes in heat transfer resulting from laser pulses and magnetic fields produced in thermoelastic materials under initial stress. This paper introduces a novel approach to modeling generalized thermoelastic materials by including fractional time derivatives with Eringen's non‐local thermoelastic theory. This model incorporates both the Caputo–Fabrizio and the Atangana–Baleanu derivatives, which are novel forms of fractional derivatives in the domain of fractional calculus. Analytical formulations for system variables, such as temperature and thermal stress, were derived using the Laplace transform method. This was done considering the effects of laser pulses, non‐local actuators, and fractional actuators. The findings of these investigations are showcased through numerical illustrations and visual representations. The research also included comparisons between the acquired results and those derived from earlier theories, which may be regarded as a specific instance. Validating the suggested model and showing its correctness and applicability is seen as a crucial step. [ABSTRACT FROM AUTHOR]

Understanding the biothermal response of skin tissue exposed to electromagnetic (EM) radiation and variable thermal fields is crucial for mitigating risks associated with such exposures. This knowledge can empower the development of safe and efficacious evidence‐based treatments for various skin conditions within the medical field. This study employs the fourth‐order Moore–Gibson–Thomson (MGT) concept to establish a theoretical framework for biothermal analysis. This investigation aims to elucidate the biothermal response of skin tissues to EM radiation. The developed model facilitates the prediction of thermal reactions within human skin and the subsequent evaluation of bioheat transfer efficiency in biological tissues. The proposed model is implemented on a one‐dimensional representation of a skin layer and incorporates the effects of an induced electric field and a time‐harmonic heat source. Additionally, a linear dependence of metabolic heat generation on tissue temperature is considered. By employing Laplace transforms, the analytical solutions for tissue temperature are presented. The derived analytical solutions are compared with established theories to assess the accuracy of the proposed model. The results reveal that the modified MGT bioheat transfer model predicts lower temperatures compared to the conventional Pennes model, attributable to the incorporation of the thermal relaxation time constant. [ABSTRACT FROM AUTHOR]

The present study examines the lateral thermal vibrations of a nanobeam subjected to an axial motion while being influenced by a sinusoidal thermal load. The partial differential equation describing the system was obtained using the extended Hamiltonian principle. Also considered were the Euler‐Bernoulli (EB) beam, the nonlocal couple stress theory, and Eringen's nonlocal elasticity model. This type of axially moving beam has multiple applications in design, including industrial, civil, structural, chemical, and computer engineering. The Laplace transform technique is utilized to translate partial differential equations into a thermoelastic differential equation of the sixth order. This study investigates the impact of nanobeam size and velocity on thermo‐mechanical characteristics. To explore the impacts of axial velocity, pulse width, nonlocal index, material length scale coefficient, and phase lag coefficients on the examined studied fields, such as lateral vibration and temperature change for the moving nanobeam are calculated. The specified factors were discovered to impact the flexibility and dynamic response of the nanobeam substantially. [ABSTRACT FROM AUTHOR]

This article offers the first investigation into the thermoelectric vibration of microscale Euler‐Bernoulli beams resting on an elastic Winkler base. We developed the system of equations for thermoelastic microbeams using elastic basis theory and the generalized Moore–Gibson–Thompson (MGT) thermal transport framework with a single‐phase delay. At the front of the microbeam, a graphene strip connected to an electrical power source was employed to generate heat. In addition, the influence of an ultra‐short‐pulsed laser on the vibration of a microbeam is studied, taking into account its heating effect. The microbeam system variables were analyzed after solving the mathematical equations by applying the Laplace transform technique. Graphs showing how different inputs affect different mechanical fields, such as Winkler substrate stiffness, voltage, electrical resistance, and temperature modulus pulses, are also presented. An increase in the Winkler modulus and the shear modulus of the foundation was found to decrease the amount of deflection and axial deformation in the microbeams. The increased beam stiffness has resulted in this decrease. [ABSTRACT FROM AUTHOR]

Many challenges in different applied fields of research, such as materials science, viscoelasticity, biological sciences, physics, and mechanical engineering, require the study of derivative operators using single singular or nonsingular kernels. Atangana and Baleanu (AB) constructed a novel fractional derivative without a singular kernel based on the extended Mittag–Leffler function to overcome the singular kernel problem seen in previous definitions of fractional‐order derivatives. In this article, we provide a novel mathematical thermoelastic heat conduction model that includes the fractional AB derivative operators. In addition, the Moore–Gibson–Thompson (MGT) equation has been incorporated into the proposed heat transport model. The proposed model has been applied to study an infinite orthotropic material with a cylindrical aperture, and the thermal conductivity coefficient of the body depends on the temperature change. The Laplace transform approach has been used to solve the system of governing partial differential equations (PDEs). To assess the validity of the proposed model and for the purposes of comparison, the numerical results have been depicted in figures as well as in tables. [ABSTRACT FROM AUTHOR]

Rotating micromachined beams are one of the most practical devices with several applications from power generation to aerospace industries. Moreover, recent advances in micromachining technology have led to huge interests in fabricating miniature turbines, gyroscopes and microsensors thanks to their high quality/reliability performances. To this end, this article is organized to examine the axial dynamic reaction of a rotating thermoelastic nanobeam under a constant‐velocity moving load. Using Eringen's nonlocal elasticity in conjunction with Euler–Bernoulli theory and Hamilton's principle, the governing equations are derived. It is assumed that the nanobeam is affected by thermal load and the boundary condition is simply supported. The Laplace transform approach is employed to solve the partial differential equations. A numerical example is presented to analyze the effects of the nonlocal parameter, rotation speed and velocity of the static moving load on the dynamic behavior of the system. The numerical results are graphically illustrated and analyzed to recognize the variations of field variables. Finally, in some special cases, our results are compared to those reported in the literature to demonstrate the reliability of the current model. [ABSTRACT FROM AUTHOR]

The current paper has been presented to illustrate the thermoelastic vibration of a rotating microbeam based on generalized thermoelasticity theory, taking into account Euler–Bernoulli's assumptions. Using Hamilton's principle, the equation of motion of the initially stressed rotating microbeams has been derived. The microbeam is exposed to femtosecond laser pulses and sinusoidal varying heat. The Laplace transform technique is applied to obtain an analytical solution to the field variables. The influence of properties of various parameters, such as axial load, laser pulse duration, angular velocity, and material variation on the thermal and elastic waves of the rotating microbeam has been displayed graphically and discussed in detail. [ABSTRACT FROM AUTHOR]

The purpose of this work is to investigate the influences of viscosity and the variation of thermal conductivity on the thermoelastic vibrations in a very thin hollow cylinder. The generalized thermal model has been developed using the Moore Gibson‐Thompson (MGT) equation by adding relaxation time in the developed Fourier law according to Green‐Naghdi theories. In addition to the initial conditions, some boundary conditions have been taken into consideration on the inner and external surface of the hollow solid cylinder. Unlike many problems in which the coefficient of thermal conductivity is assumed to be constant, it has been taken into account that it is variable and depends on the change of temperature. By applying the Laplace transform method, the numerical solutions are assigned to the studied physical quantities. The studied quantities have been presented graphically and in tabular form to compare the outcomes for various models of thermoelasticity and to illustrate the influences of changing thermal properties and viscosity on the physical fields. [ABSTRACT FROM AUTHOR]