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The present article studies the two phase local/nonlocal deformation of magneto thermo electrical composite nano beam reinforced with graphene oxide powder (GOP). The controlling equation of motion and boundary conditions are derived via two phase elasticity in differential form conjunction with Hamilton's principle and Euler-Bernoulli beam model. The effect of a non-uniform magnetic and piezo electric field is incorporated with the governing equations by convoluting field quantities and displacement components. Then, Navier method is adopted to observe the influence of various boundary conditions on the dynamics of the beam. Comparison studies are performed to display the accuracy and efficiency of this analytical model. Further, the effects of magnetic field, GOP weight fraction, two phase parameter, external electric voltage, nonlocal parameter and temperature difference on the dimensionless frequency of GOP reinforced magneto piezo thermo elastic composite beams are thoroughly investigated and highlighted through tables and dispersion curves. [ABSTRACT FROM AUTHOR]

This composition presents a multi-phase-lags thermos-elasticity model for the thermos-elastic wave propagation reaction of a composite hollow circular cylinder with the interface layer LEMV/CFRP (Linear Elastic Material with void/Carbon Fiber Reinforced Polymer) using new modified couple stress theory. Three partial differential equations of the modified couple stress and multiphase lag model of composite hollow cylinder are derived for axisymmetric mode and solved exactly using linear theory of elasticity. The frequency equations are achieved for the traction free outer surface with continuity conditions at the interfaces. The influences of changing wave number and thickness on the field quantities like frequency, temperature, displacements, are investigated. Some comparisons are tabulated and presented graphically to estimate the effects of various thermos-elasticity theories and coupled stress parameter. [ABSTRACT FROM AUTHOR]

This study investigates the vibration of non-homogeneous porous Euler nanobeams, incorporating the governing equations of Eringen's nonlocal elasticity theory. To enhance computational efficiency in our analysis, we employ the Rayleigh-Ritz method, harnessing computationally efficient Bernstein polynomials as shape functions. Furthermore, we explore a range of classical boundary conditions tailored to address the specific problem at hand. In order to validate our findings, we conduct a comparative analysis against existing literature, thereby underscoring the effectiveness and robustness of our proposed methodology. Our research also places a significant emphasis on elucidating the impact of scaling parameters, dimensionless amplitude and porosity, on dimensionless frequency under various boundary conditions, including Simply-Supported (S-S), Clamped-Simply Supported(C-S), and Clamped-Clamped(C-C) configurations. [ABSTRACT FROM AUTHOR]

In this study, the effect of nonlocal scale value and two phase lags on the free vibration of generalized thermoelastic multilayered LEMV (Linear Elastic Material with Voids)/CFRP (Carbon Fiber Reinforced Polymer) composite cylinder is studied using nonlocal form of linear theory of elasticity. The governing equation of motion is established in longitudinal axis and variable separation model is used to transform the governing equations into a system of differential equations. To investigate vibration analysis from frequency equations, the stress free boundary conditions are adopted at the inner, outer and interface boundaries. The graphical representation of the numerically calculated results for frequency shift, natural frequency, and thermoelastic damping is presented. A special care has been taken to inspect the effect of nonlocal parameter on the aforementioned quantities. The results suggest that the nonlocal scale and the phase lag parameters alter the vibration characteristics of composite cylinders significantly. [ABSTRACT FROM AUTHOR]

Thermal bifurcation studies are conducted on piezoelectric humid thermal piezoelectric foam nanobeam with voids. Various porosity designs are considered for the proposed structure. By synthesis the piezoelectric and humid thermal parameters with field component and displacement variables, the fundamental equations that governs the present study have been equipped. The finite element technique with developed beam model is applied to obtain the solution of the nanobeam. The authentication of this analytical model is tested with exiting literature. The strength of the nanobeam is improved by performing a detailed parametric study on physical variables and highlighted with plots and tables. [ABSTRACT FROM AUTHOR]

This study explores the propagation of S-waves in a layered medium characterized by anisotropy, non-homogeneity, incompressibility, pre-existing stress, and couple stress effects. The frequency equation that determines the phase velocity of shear waves, incorporating linear inhomogeneities, has been derived. Using numerical computations in MATLAB, the effects of varying initial stress, density, anisotropy, rigidity, and couple stress parameters on wave propagation are analysed. The findings are presented graphically, providing insights into how these factors influence phase velocity and improving our understanding of wave behaviour in complex media. These findings are not only instrumental in advancing fundamental understanding but also hold practical significance across diverse applications. For instance, in geotechnical engineering, this knowledge can inform the design of robust infrastructure capable of withstanding seismic events. In material science and manufacturing, they facilitate the development of resilient materials and structures. [ABSTRACT FROM AUTHOR]

This article studies a new analytical method for clamped free generalized thermoelastic waves in a doubly connected polygonal ring reinforced with graphene platelets under the exact heat conduction equation with delay. The plain strain model of generalized thermoelastic polygonal ring of homogeneous isotropic is considered. Four different distribution patterns are considered via Eshelby–Mori–Tanaka homogenizing idea. The complex characteristic equations are obtained through the nonlinear surface of the grapheme platelets reinforced composite (GPLRC) ring by using Fourier expansion collocation method. The triangular, square, pentagonal and hexagonal GPLRC ring is evaluated via numerical values. The results of the physical variants like stress, strain, and mechanical displacement, weight fraction of grapheme platelets (GPL), dimensionless frequency and temperature rise are explored in tabular and graphical form. Some validations are presented between the frequency of square cross section plates and peer-reviewed literature to show the accuracy and the convergence of this method. These results can be beneficial to design thermal polygonal composite GPL ring structures in diverse environments. [ABSTRACT FROM AUTHOR]

In this paper, the wave propagation in a rotating disc of polygonal crosssection immersed in an inviscid fluid is studied using the Fourier expansion collocation method. The equations of motion are derived based on two-dimensional theory of elasticity under the assumption of plane strain-rotating disc of polygonal cross-sections composed of homogeneous isotropic material. The frequency equations are obtained by satisfying the boundary conditions along the irregular surface of the disc using Fourier expansion collocation method. The triangular, square, pentagonal and hexagonal cross-sectional discs are computed numerically for Copper material. Dispersion curves are drawn for non-dimensional wave number and relative frequency shift for longitudinal and flexural (symmetric and anti-symmetric) modes. This work may find applications in navigation and rotating gyroscope. [ABSTRACT FROM AUTHOR]

Wave propagation in heat conducting thermo elastic plate of elliptical cross-section is studied using the Fourier expansion collocation method based on Suhubi's generalized theory. The equations of motion based on two-dimensional theory of elasticity is applied under the plane strain assumption of generalized thermo elastic plate of elliptical cross-sections composed of homogeneous isotropic material. The frequency equations are obtained by using the boundary conditions along outer and inner surface of elliptical cross-sectional plate using Fourier expansion collocation method. The computed non-dimensional frequency, velocity and quality factor are plotted in dispersion curves for longitudinal and flexural (symmetric and antisymmetric) modes of vibrations. [ABSTRACT FROM AUTHOR]

Abstract: This work investigates the three dimensional wave propagation of a homogeneous transversely isotropic magneto thermo elastic cylindrical panel in the context of the linear theory of thermo elasticity. Three displacement potential functions are introduced to uncouple the equations of motion. A Bessel function solution with complex arguments is directly used to analyze the frequency equations with traction-free boundary conditions. The special cases have also been deduced for magneto elastic, thermo elastic and elastokinetic at various levels from the present analysis. The numerical example which demonstrates the present method is studied for the material magnetostrictive cobalt iron oxide (CoFe2O4). The computed non-dimensional phase velocity and attenuation coefficient are plotted in the form of dispersion curves. The coupling effect among thermal, magnetic and elastic in magneto thermo elastic material provides a mechanism for sensing thermo mechanical disturbances in the design of sensors and surface acoustic damping filters. [Copyright &y& Elsevier]

In this article the three-dimensional dispersion analysis of a homogeneous transversely isotropic magneto generalized thermoelastic cylindrical panel is discussed in the context of the linear theory of generalized thermoelasticity. Three displacement potential functions are introduced to uncouple the equations of motion. A Bessel function solutions with complex argument is used directly to analyze the frequency equations with traction-free boundary conditions and the special cases have also been deduced for magneto-elastic, thermoelastic and elasto-kinetic at various levels from the present analysis. Finally the numerical example demonstrates the present method and is studied for the material magnetostrictive cobalt iron oxide (CoFe2O4). The computed non-dimensional phase velocity, attenuation coefficient, specific loss and thermo-mechanical coupling factor are plotted in the form of dispersion curves with the support of MATLAB. [ABSTRACT FROM AUTHOR]

This paper is concerned with the exponential synchronization of Lur’e type complex dynamical networks with uncertain coupling strength. A novel pinning impulsive controller is designed to achieve synchronization, in which, only selection of nodes are chosen to control instead of the whole network. In addition, the proposed control scheme is digital and it can lead to low installation cost and less time. In order to realize synchronization of Lur’e type complex dynamical networks, crucial delay-dependent stability conditions are derived by utilizing Lyapunov functional together with information of the time-varying delay and convex combination technique. The resulting stability conditions are formulated in the form of linear matrix inequalities (LMIs) and by solving the obtained LMIs, desired impulsive control gain matrices are calculated, which are capable to guarantee the exponential stability of error system. Finally, the effectiveness of the proposed method is demonstrated through numerical simulations. [ABSTRACT FROM AUTHOR]