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Purpose: As the micropolar thermoelasticity theory predicted, flexible materials can experience significant vibration, temperature variations, and microrotations due to transitional and rotational motions. This study presents a new micropolar thermoelasticity theory with a two-phase delay of high-order and two temperatures. The proposed model has been used to study the microstructure of rotating materials when their atomic or molecular vibrations change under the effects of Hall current. There is an assumption that the angular velocity of an elastic medium is always the same. Methods: The proposed problem was solved and analyzed using the normal mode approach. For the purpose of analysis and comparison, the theoretical results of deformations, temperatures, and other fields are provided and graphically depicted. Results and Conclusions: The results showed that the higher-order phase delays and the two-temperature factor significantly affected the behavior of all studied variables. [ABSTRACT FROM AUTHOR]

In this study, the Moore–Gibson–Thompson (MGT) concept of thermal conductivity is applied to a two-dimensional elastic solid in the form of a half-space. This model was constructed using Green and Naghdi's thermoelastic model to address the infinite velocity problem of heat waves. It has been taken into account that the free surface of the medium is immersed in an electromagnetic field of constant intensity, undergoes thermal shock, and rotates with a uniform angular velocity. The governing equations of a modified version of Ohm's law account for the impact of temperature gradients and charge densities. By using the method of normal mode analysis, an analytical representation of the studied physical fields was obtained. The effect of rotation and the modulus of modified Ohm's law on the responses of the field distributions examined is discussed, along with accompanying graphical representations. Other thermoelastic models have been compared with the results of the proposed system when the relaxation time is ignored. [ABSTRACT FROM AUTHOR]

This paper introduces size-dependent modeling and investigation of the transverse vibrational behavior of rotating thermoelastic nanobeams by means of nonlocal elasticity theory. In the formulation, a model of thermal conductivity with two-phase delays (DPL) was utilized. By incorporating the interactions between phonons and electrons, this model took into account microstructural influences. Also, we have employed the state-space approach and Laplace transform approach to solve the governing equations, which were developed in the context of the nonlocal Eringen model. The nanobeam material is subjected to a changeable temperature field produced by the graphene tape attached to the nanobeam and connected to an electrical source. In addition, the nanobeam material is fully encompassed by an axially applied magnetic field. It has been revealed how coefficients such as the rotational angular velocity of the nanobeam, nonlocal coefficient, voltage, electrical resistance, and applied magnetic field influence its behavior. [ABSTRACT FROM AUTHOR]

In this article, the importance of studying the behavior of small-scale rotating materials and structures is highlighted for its valuable contribution to many scientific and engineering fields. As a result, these types of microbeams have been studied using nonlocal elasticity theory (NET) and modified couple stress (MCST) models, as well as Euler–Bernoulli assumptions for thin beams. The temperature-dependent heat conduction model and the Moore–Gibson–Thompson (MGT) model of heat transfer are also integrated. The effects of nonlocal properties, length scale, thermal conductivity factor fluctuation, the angular velocity of rotation, and thermal parameters on the behavior of the studied variables were investigated. The results were validated and applicable, and the data were systematically compared with previous literature and other investigators. The results show that the materials behave differently at the nanoscale than the results of the usual continuum mechanics approach due to taking into account nonlocal and length-scale effects. [ABSTRACT FROM AUTHOR]

In this work, we extend the modification of the generalized theories of thermoelasticity and photothermal. In this context, a new model has been derived based on the Moore-Gibson-Thompson (MGT) equation and combining the two models of thermoelasticity with one relaxation time (Lord-Shulman) and the theory of Green-Naghdi of the third type (GN-III). One of the most important features of the proposed model is that it predicts limited speeds of thermal signals and photovoltaic waves. The proposed model has been applied to examine the interactions between plasma, thermal, and elastic processes within a solid semiconductor sphere. It was taken into account that the sphere rotates with a constant angular velocity around its axis, is surrounded by an external magnetic field, and is also subjected to thermal shock. The singularities encountered in different physical fields have been addressed in the center and poles of the sphere. The influence of rotation and carrier lifetime parameters on different physical properties of semiconductor materials has been graphically displayed and explained using the Laplace method. [ABSTRACT FROM AUTHOR]

This paper analyzes the thermoelastic dynamic behavior of simply supported viscoelastic nanobeams of fractional derivative type due to a dynamic strength load. The viscoelastic Kelvin–Voigt model with fractional derivative with Bernoulli–Euler beam theory is introduced. The generalized thermoelastic heat conduction model with a two-phase lag is also used. It is assumed that the beam is rotating at a uniform angular velocity and that the thermal conductivity varies linearly depending on the temperature. Due to a variable harmonic heat and retreating time-dependent load, the nanobeam is excited. The Laplace integral transformation technique is used as the solution method. The thermodynamic temperature, deflection function, bending moment, and displacement are numerically calculated. Results of fractional and integer viscoelastic material models are compared. In the studied system, the effect of the nonlocal parameter, viscosity and varying load on the solutions is shown, and the temperature-dependence of the thermal conductivity is analyzed. [ABSTRACT FROM AUTHOR]

• The study of a rotating viscoelastic thin microbeam. • Capturing the influences of viscoelastic behavior via a non-Fourier heat conduction model. • To incorporate the viscoelastic properties of the model in terms of the Kelvin-Voigt scheme. • To reduce the new viscoelastic microbeam model to the elastic beam theory. • The effect of the viscous damping coefficient on the microbeam structure. In this investigation, the system of equations governing the thermoelastic behavior of a rotating viscoelastic microbeam has been derived based on the non-Fourier heat conduction model. The viscoelastic properties of the material are incorporated in terms of the Kelvin-Voigt scheme. This considered microbeam is axially compressed and rotated at a uniform angular velocity in addition to exposing it to a femtosecond laser pulse heat source. The proposed model can be reduced to the thermoelastic beam theory when the viscous and rotation parameters are neglected. To obtain an analytical solution for the studied fields, the Laplace transform technique is applied. The effect of the viscous damping coefficient on the microbeam structure has been studied. Also, the effect of the axial load, laser pulse duration and angular velocity on the thermal and elastic waves of the rotating microbeam has been presented graphically and analyzed in detail. [ABSTRACT FROM AUTHOR]