Showing papers in "International Journal of Engineering Science in 2018"

TL;DR: A critical review of nonlinear techniques which have been investigated for performance enhancement of energy harvesters in the past decade and the present state of the art of energy Harvesters which utilise this technique is conducted.

TL;DR: In this article, a size-dependent continuum-based model is presented for the coupled nonlinear dynamics of extensible functionally graded (FG) microbeams with viscoelastic properties.

TL;DR: In this paper, the nonlocal elasticity and nonlocal strain gradient elasticity have been employed to estimate the mechanical behavior of nanostructures, and the results of size-dependent wave propagation analyses are discussed.

TL;DR: In this article, the longitudinal free vibration behaviors of one-dimensional nanostructures with various boundary conditions are investigated based on Eringen's nonlocal theory and the governing differential equation of motion is analytically solved for a number of different boundary conditions like clamped, free, attached mass and/or spring.

TL;DR: In this paper, a generalized Bernoulli-Euler and Timoshenko sandwich beam models are derived by means of a computational homogenization technique and two additional length scale parameters involved in the models are validated by matching the lattice response in benchmark problems for static bending and free vibrations calibrating the strain energy and inertia gradient parameters, respectively.

TL;DR: In this article, the authors prove the equivalence between the nonlocal strain gradient integral model of elasticity and the differential problem with boundary conditions and provide a viable approach to study size-dependent phenomena in nano-beams of applicative interest.

TL;DR: In this article, a consistent stress-driven nonlocal integral model for nonisothermal structural analysis of elastic nano-and microbeams is proposed, which is equivalent to an adequate set of differential equations, accompanied by higher-order constitutive boundary conditions, when the special Helmholtz averaging kernel is adopted in the convolution.

TL;DR: In this paper, the size-dependent nonlinear oscillation characteristics of a functionally graded microplate are investigated numerically, in which all the displacements, i.e., in-plane as well as out-of-plane, and their inertia are accounted for.

TL;DR: In this paper, the size-dependent axial and flexural free vibrations of Bernoulli-Euler nano-beams are investigated by the modified nonlocal strain gradient elasticity model presented in (Barretta & Marotti de Sciarra, 2018).

TL;DR: In this paper, the pull-in characteristics of a microplate-based microelectromechanical system (MEMS) are investigated via a multi-degree freedom energy-based technique where the in-plane and out-of-plane motions are retained in the modelling and simulations.

TL;DR: In this article, a nonlocal strain gradient beam model incorporating the thickness effect is developed for the size-dependent buckling analysis of nanobeams, and closed-form solutions are derived for post-buckling configuration and critical buckling force.

TL;DR: In this paper, a non-classical nonlinear differential equation of motion of the nanoscale tube is obtained using Hamilton's work/energy principle together with the nonlocal strain gradient elasticity.

TL;DR: In this article, the vibration behaviors of porous nanotubes are investigated for the first time and the nonlocal strain gradient theory in conjunction with a refined beam model are employed to formulate the size-dependent model.

TL;DR: In this paper, the free vibration of three-directional functionally graded material (TDFGM) Euler-Bernoulli nano-beam, with small scale effects, is investigated.

TL;DR: In this paper, the size-dependent free vibration of functionally graded viscoelastic (FGV) nanobeams including the simultaneous effects of the microstructure rotation and surface energy for the first time was addressed.

TL;DR: In this article, a hierarchical lattice topology was proposed to increase the energy absorbing ability of tubular structures without increasing the weight, and three typical folding styles, i.e., macrocell folding, micro-cell folding and hybrid folding were observed in both experiments and finite element (FE) simulations.

TL;DR: In this article, a non-local nonlinear analysis of functionally graded plates subjected to static loads is studied, and the nonlinear displacement finite element model of the resulting governing equations is developed, and Newton's iterative procedure is used for the solution of nonlinear algebraic equations.

TL;DR: In this paper, a nonlocal strain gradient elasticity approach is proposed for the mechanical behavior of fluid-conveying nanotubes; a nonlinear analysis, incorporating stretching, is conducted for a model based on both a non-local theory along with a strain gradient one, and the energy minimisation is conducted via Hamilton's method for an oscillating nanotube subject to external forces.

TL;DR: In this paper, the prediction of vibration characteristics of two-dimensional functionally graded (2D-FG) tubes based on higher order theory is paid to the vibration properties of two different materials, and the material properties of the nano-scaled tubes vary both in the length and radial direction.

TL;DR: In this paper, size-dependent Kirchhoff and Mindlin plate models are developed to investigate the coupling effects of nonlocal stress, strain gradient and surface energy on the dynamic response of nanoplate.

TL;DR: In this paper, an analysis of forced vibration of a porous functionally graded (FG) nanoshell is conduced employing a two-parameter non-classical elasticity theory called nonlocal strain gradient theory.

TL;DR: In this paper, a comprehensive study on vibration behavior of double-layered nanobeam systems (DNBS) is presented within the framework of Eringen's two-phase local/nonlocal integral model.

TL;DR: In this article, a size-dependent Timoshenko beam model is used for free vibration and instability analysis of a nanotube conveying nanoflow, where the extended Hamilton's principle is employed to obtain the sizedependent governing equations of motion.

TL;DR: In this article, the authors study the mechanical behavior of soft rubber-like digital materials used in polyjet multi-material 3D-printing to create deformable composite materials and flexible structures.

TL;DR: In this paper, an analytic model of porous nanotubes for the wave propagation analysis is formulated with the help of the nonlocal strain gradient theory, and the dispersion relations between phase velocity and wave number are determined by solving an eigenvalue problem.

TL;DR: In this article, a multiscale micromechanical modeling approach is developed to predict elastic properties of carbon fiber (CF)-reinforced polymer hybrid composites, where the unidirectional fibers are coated with randomly oriented carbon nanotubes (CNTs).

TL;DR: In this paper, the authors provided an exact solution for the size dependent buckling and post-buckling behavior of functionally graded (FG) micro-beams with arbitrary boundary conditions which are subjected to combined thermo-mechanical loading.

TL;DR: A dynamic three-dimensional visco/hyperelastic fluid–structure interaction model of an atherosclerotic coronary artery developed by means of the finite element method (FEM) using ANSYS can potentially be used as a predictive tool for plaque rupture to identify the conditions that are high risk for atherosclerosis plaque rupture.

TL;DR: In this paper, the modified couple stress theory can be applied for micro-and nano-scales, if the material length scale parameter is individually calculated for these scales, and the hardening and softening effects of the MCS theory are investigated.

TL;DR: In this paper, the nonlinear large-amplitude static and dynamic responses of a doubly curved shallow microshell in the framework of the modified couple stress (MCS) theory were examined.