Article
Mathematics, Applied
Hayri Metin Numanoglu, Hakan Ersoy, Bekir Akgoz, Omer Civalek
Summary: This study investigates the size-dependent thermo-mechanical vibration analysis of nanobeams by implementing Hamilton's principle and the stress equation of nonlocal elasticity theory. The finite element method is used to solve the eigenvalue problem and derive stiffness and mass matrices. Nonlocal finite element method is emphasized for analyzing the vibration behavior of nanobeams under different boundary conditions.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2022)
Article
Mechanics
H. M. Numanoglu, H. Ersoy, O. Civalek, A. J. M. Ferreira
Summary: This article examines the free thermal vibration analysis of nanobeams surrounded by an elastic matrix using nonlocal elasticity and Timoshenko beam theories. The equation of motion for free vibration is solved by analytical method, and a weighted residue-based finite element formulation is developed for boundary conditions other than simply supported nano beams. Numerical results show the high accuracy of the nonlocal finite element formulation and the effects of size dependency and environmental factors on the dynamic behavior of nanobeams are discussed in detail.
COMPOSITE STRUCTURES
(2021)
Article
Engineering, Civil
Mouayed H. Z. Al-Toki, Hayder A. K. Ali, Nadhim M. Faleh, Raad M. Fenjan
Summary: In this research, the dynamic stability behavior of nonlocal beams on an elastic foundation has been numerically assessed. The beams are made of functional graded porous material and are exposed to thermal and humid environments. The study also considers the beams subjected to axial periodic mechanical load, which leads to instability behavior. The governing equations are established using nonlocal elasticity and solved using the Chebyshev-Ritz-Bolotin method. The stability boundaries of the beams are significantly influenced by temperature and moisture variation, as well as the amount of porosities inside the material.
GEOMECHANICS AND ENGINEERING
(2022)
Article
Mechanics
Quoc-Hoa Pham, Phu-Cuong Nguyen, Trung Thanh Tran
Summary: The main goal of this study is to investigate the dynamic response of sandwich nanoplates with a porous functionally graded (PFG) core using isogeometric analysis (IGA) and higher-order shear deformation theory (HSDT). The small-scale effect in nanostructures is taken into account by employing the nonlocal elasticity theory. The proposed method is validated by comparing the numerical results with published works, and some examples are conducted to examine the influence of parameters on the dynamic response of the sandwich nanoplates with the PFG core.
COMPOSITE STRUCTURES
(2022)
Article
Mathematics, Applied
Roshan Lal, Chinika Dangi
Summary: This article introduces a nonlocal model based on the Timoshenko beam theory for vibration response of bi-directional functionally graded moderately thick nanobeam under surface effect. The study considers surface and nonlocal effects using the Gurtin-Murdoch surface elasticity theory and Eringen's nonlocal theory, and numerical results are obtained using the differential quadrature method.
APPLIED MATHEMATICS AND COMPUTATION
(2021)
Article
Materials Science, Multidisciplinary
A. Czekanski, V. V. Zozulya
Summary: New higher-order models based on the linear theory of nonlocal elasticity are developed for plane rods and beams. These models are used to analyze tension-compression and transverse bending modes of nonlocal rod and beam vibration. By considering nonlocal effects, the proposed models can be applied to vibration analysis of rods and beams at macroscales, microscales, and nanoscales.
MECHANICS OF ADVANCED MATERIALS AND STRUCTURES
(2021)
Article
Computer Science, Interdisciplinary Applications
Mahsa Najafi, Isa Ahmadi
Summary: In this paper, an efficient method based on nonlocal elasticity theory and Layerwise theory is proposed for the analysis of bending, buckling, and vibration of functionally graded nanobeam. The method takes into account the transverse shear and normal strains of nanobeam and the small-scale effect. The proposed theory is validated by comparing with other theories and shows accurate results in predicting vibration, buckling, and bending of nanobeams.
ENGINEERING WITH COMPUTERS
(2023)
Article
Mechanics
Behnam Daraei, Saeed Shojaee, Saleh Hamzehei-Javaran
Summary: In this study, thermo-mechanical analysis of functionally graded material beams using micropolar theory is conducted based on the higher-order model in the framework of the Carrera unified formulation (CUF). The analysis considers the nonhomogeneous mechanical and thermal properties of the beams and takes into account the effect of the nonlinear temperature rise profile. Numerical examples demonstrate the influence of thermal loadings, power law indexes, orders of expansion and boundary conditions on the results. The equations can be applied to analyze beam structures in macro-, micro-, and nano-scale by considering micropolar couple stress and micro-rotation effects.
ARCHIVE OF APPLIED MECHANICS
(2023)
Article
Construction & Building Technology
Mahsa Najafi, Isa Ahmadi
Summary: A nonlocal Layerwise theory is proposed for free vibration analysis of nanobeams resting on an elastic foundation, considering small-scale effects and predicting more accurate results. Effects of nonlocal parameter, Pasternak shear coefficient, Winkler spring coefficient, and boundary conditions on the vibration of nanobeams are studied. The theory can be applied to analyze the mechanical behavior of various nanostructures with different loading and boundary conditions.
STEEL AND COMPOSITE STRUCTURES
(2021)
Article
Mechanics
S. Ali Faghidian, Esmaeal Ghavanloo
Summary: The unified higher-order theory of two-phase nonlocal gradient elasticity is proposed by introducing higher-order nonlocality to the higher-order gradient theory of elasticity. Nonlocal approaches are used to simulate long-range interactions at the nano-scale, with equivalence between the constitutive law's integral convolutions and the nonlocal gradient differential formulation confirmed through non-classical boundary conditions.
Article
Computer Science, Interdisciplinary Applications
Pei-Liang Bian, Hai Qing
Summary: In this study, a new FEM framework was developed to simulate the mechanical responses of the Euler-Bernoulli beam with a two-phase local/nonlocal mixed model. The model showed efficient convergence, simplicity of expressions, and flexibility in handling various boundary conditions and external loads.
ENGINEERING WITH COMPUTERS
(2023)
Article
Mechanics
Mohamed-Ouejdi Belarbi, Mohammed-Sid-Ahmed Houari, Ahmed Amine Daikh, Aman Garg, Tarek Merzouki, H. D. Chalak, Hicham Hirane
Summary: An efficient nonlocal finite element model was developed to study the bending and buckling behavior of functionally graded nanobeams. The new theory provides accurate transverse shear stress distribution without the need for correction factors, showing high accuracy and convergence rate. Detailed numerical studies validated the performance and reliability of the proposed model.
COMPOSITE STRUCTURES
(2021)
Article
Engineering, Multidisciplinary
Isa Ahmadi
Summary: This study investigates the free vibration of a multiple-nanobeam system under various edge boundary conditions and the number of coupled nanobeams. The Eringen's nonlocal elasticity theory is used to take into account the size effect, and the governing equations of the coupled beams are obtained using the Timoshenko beam theory. A meshless formulation is presented to discretize the equations into a set of ordinary differential equations in the time domain. The accuracy of the results is confirmed by comparing them with available analytical results in the literature, showing good agreement. The numerical results present the free vibration frequencies and mode shapes of the multiple-nanobeam system under various edge boundary conditions, and investigate the effects of parameters such as coupling stiffness, nonlocal parameters, and number of nanobeams. This method is useful for analyzing multiple-nanobeam systems with arbitrary number of nanobeams, arbitrary boundary conditions, coupling stiffness, and length to thickness ratio.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2022)
Article
Engineering, Mechanical
Ahmed E. Abouelregal, Hamid Mohammad-Sedighi, Seyed Ali Faghidian, Ali Heidari Shirazi
Summary: This article investigates the influence of thermal conductivity on the dynamics of a rotating nanobeam using nonlocal thermoelasticity theory. Analytic solutions for bending moment, deflection, and temperature are obtained through the Laplace transform procedure. The study highlights the strong dependence of physical fields on nonlocal parameters, changes in thermal conductivity, rotation speed, and mechanical loads, emphasizing the importance of considering these effects in the manufacturing process of precise/intelligent machines and devices.
FACTA UNIVERSITATIS-SERIES MECHANICAL ENGINEERING
(2021)
Article
Physics, Multidisciplinary
Chinika Dangi, Roshan Lal
Summary: A nonlocal model has been proposed to study the vibration behavior of bi-directional functionally graded nanobeam, considering surface and size effects. The results show that the surface effect plays an important role in such material.
Article
Mechanics
Farzad Ebrahimi, Sepehr Bayrami Sedighi
Summary: In this paper, a sandwich composite plate with a tunable magneto-rheological (MR) fluid core was used to analyze wave propagation. The effects of magnetic field and core-to-top layer thickness ratio on the wave dispersion characteristics were investigated. The results showed that the magnetic field intensity was the most important factor in changing the wave dispersion characteristics, and increasing the core-to-top layer thickness ratio led to a decrease in wave frequency.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2022)
Article
Mechanics
Reza Asrari, Farzad Ebrahimi, Mohammad Mahdi Kheirikhah, Keivan Hosseini Safari
Summary: This article investigates the buckling characteristics of a functionally graded magneto-electro-thermo-elastic nanoshell based on the nonlocal strain gradient theory. The nanoshell is subjected to external fields, and the governing equations are derived and solved using Galerkin's approach, exploring the dependence of buckling behavior on various factors.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2022)
Article
Mechanics
Ali Shokrgozar, Aria Ghabussi, Farzad Ebrahimi, Mostafa Habibi, Hamed Safarpour
Summary: In this study, the stability of a cylindrical microshell reinforced by graphene nanoplatelets under axial load is investigated, taking into account the viscoelastic foundation and nonlocal strain gradient theory. The research considers the effects of various boundary conditions and explores the impact of viscoelasticity, strain-stress size-dependent parameters, and other factors on the stability of the microshell. The results provide valuable insights for the design and fabrication of microactuators and microsensors.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2022)
Article
Computer Science, Interdisciplinary Applications
Ali Dabbagh, Abbas Rastgoo, Farzad Ebrahimi
Summary: This paper analyzes the post-buckling behaviors of multi-scale hybrid nanocomposite beam-type structures manufactured from carbon fibers and carbon nanotubes, considering the influences of agglomeration phenomenon and initial deflection. Nonlinear governing equations are derived based on the combination of the virtual work's principle, von Karman hypothesis, and Euler-Bernoulli beam theory, solved analytically using Galerkin's method under different boundary conditions to show the significant impact of tailoring agglomeration parameters on stability response.
ENGINEERING WITH COMPUTERS
(2022)
Article
Mechanics
Seyed Sajad Mirjavadi, Masoud Forsat, Mohammad Reza Barati, A. M. S. Hamouda
Summary: This study investigates the nonlinear free vibrations of porous functionally graded annular spherical shell segments and highlights the factors affecting the vibration characteristics.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2022)
Article
Mechanics
Seyed Sajad Mirjavadi, Masoud Forsat, Mohammad Reza Barati, A. M. S. Hamouda
Summary: This article investigates the nonlinear vibration of variable thickness cylindrical panels made of multi-scale composite materials. The study defines the elastic properties of the materials and considers the changes in panel thickness. By using Jacobi elliptic functions to solve the governing equations, the exact frequency-amplitude curves of the panels are obtained. The study also examines the effects of various factors on the frequency-amplitude curves.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2022)
Article
Mechanics
Seyed Sajad Mirjavadi, Masoud Forsat, Mohammad Reza Barati, A. M. S. Hamouda
Summary: This research examines the nonlinear free vibration behavior of truncated conical shell segments made from multi-scale epoxy/carbon nanotube/fiberglass material. A 3D Mori-Tanaka micro-mechanic method is used to define the hybrid material properties by incorporating random dispersion of carbon nanotubes and parallel alignment of glass fibers. The study focuses on the effects of fiber volume, fiber directions, semi-vertex angle, CNT weight fraction, and CNT aspect ratio on the nonlinear free vibrations of the multi-scale truncated conical shell segments.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2022)
Article
Physics, Multidisciplinary
Farzad Ebrahimi, Ali Seyfi
Summary: This paper mainly focuses on analyzing the wave propagation of sigmoid functionally graded (SFG) piezoelectric nanobeams on an elastic foundation using the nonlocal elasticity theory. The small-scale effect is considered by employing Eringen's nonlocal elasticity theory (ENET). Zinc oxide and lithium niobate are assumed to be the constituent materials of the nanoscale structure. The nonlocal governing equations of the piezoelectric nanobeam are derived using Hamilton's principle and the Euler-Bernoulli beam theory, and then solved analytically. The effects of various parameters on the wave frequency and phase velocity of the SFG piezoelectric nanobeam are examined and presented in a series of illustrations.
WAVES IN RANDOM AND COMPLEX MEDIA
(2022)
Article
Physics, Multidisciplinary
M. S. H. Al-Furjan, Mostafa Habibi, Farzad Ebrahimi, Kianoosh Mohammadi, Hamed Safarpour
Summary: This paper investigates the wave propagation behavior of a high-speed rotating laminated nanocomposite cylindrical shell using classic, strain gradient, nonlocal and nonlocal strain gradient theories. The results show that wave number, angular velocity, and different types of laminated composites have a significant impact on the phase velocity of the nanocomposite structure.
WAVES IN RANDOM AND COMPLEX MEDIA
(2022)
Article
Mechanics
Farzad Ebrahimi, Ali Dabbagh, Abbas Rastgoo
Summary: This paper investigates the buckling problem of a multi-scale hybrid nanocomposite shell for the first time while the cylinder is supposed to be rested on an elastic substrate. The effects of nanofillers' agglomeration and the equivalent material properties of the carbon nanotube-reinforced (CNTR) nanocomposite are studied. The results provide insights into the failure behavior and propose strategies to enhance the buckling resistance of the nanocomposite structure.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2023)
Article
Physics, Multidisciplinary
Farzad Ebrahimi, Ali Seyfi, Mostafa Nouraei, Parisa Haghi
Summary: The study investigates wave propagation in simply supported functionally graded beams exposed to magneto-thermal environments and embedded on two-parameter elastic foundation. The influence of various parameters on wave frequency and phase velocity of the beams is compared and thoroughly discussed to highlight key findings.
WAVES IN RANDOM AND COMPLEX MEDIA
(2022)
Article
Computer Science, Interdisciplinary Applications
M. S. H. Al-Furjan, Seyedeh Yasaman Bolandi, Mostafa Habibi, Farzad Ebrahimi, Guojin Chen, Hamed Safarpour
Summary: This study presents critical angular velocity, critical velocity of fluid flow, and vibration control analysis of a rotating multi-hybrid nanocomposite reinforced cylindrical microshell. By utilizing a non-classical model, various factors such as Coriolis and centrifugal effects, strains and stresses, and external voltage are considered. The study also applies the rule of mixtures and a modified Halpin-Tsai theory for elasticity modulus, and utilizes a Proportional-Derivative (PD) controller for sensor output control.
ENGINEERING WITH COMPUTERS
(2022)
Article
Mechanics
Mohammad Reza Barati, Hossein Shahverdi
Summary: In this article, the nonlinear free/forced vibrations of a plate undergoing large deflection and moderate rotation were investigated using Jacobi elliptic functions. The results showed that the conventional approximate solutions based on single-harmonic assumption were inadequate, while the Jacobi elliptic function method considered higher-order harmonics and provided a more accurate solution.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2023)
Article
Engineering, Chemical
Mohammad Reza Barati, Hossein Shahverdi, Behzad Hakimelahi
Summary: The research examines the nonlinear free/forced vibrational behavior of a sandwich plate with graphene platelet reinforced face sheets, proposing the use of GPL-reinforced nanocomposites to enhance mechanical performance. The study finds that the dispersion type, amount, and thickness of GPL in the face sheets can affect the free and forced vibrations of the honeycomb sandwich panel.
TRANSPORT IN POROUS MEDIA
(2022)
Article
Physics, Multidisciplinary
Mohammad Reza Barati, Hossein Shahverdi
Summary: This paper obtained the material properties of architected meta-material plates with different cell patterns through numerical calibration. An artificial neural network was developed to derive a meta-material shape factor for all possible cell geometries. Finite element simulations confirmed the theoretical model and parameter studies examined the influences of the periodic design patterns.
WAVES IN RANDOM AND COMPLEX MEDIA
(2022)
