Article
Mechanics
Chang Tao, Ting Dai
Summary: This study investigates the postbuckling behavior of sandwich cylindrical shell panels with a graphene platelet reinforced functionally graded porous core under various loads for the first time. Utilizing a combination of NURBS-based isogeometric analysis and the modified arc-length method, the study demonstrates nonlinear load-deflection responses and captures different types of instability. Parametric studies show the influences of various factors on the load-deflection behavior of the panels.
COMPOSITE STRUCTURES
(2021)
Article
Engineering, Civil
Vuong Nguyen Van Do, Chin-Hyung Lee
Summary: This study investigates the thermal-induced post-buckling behavior of thin-walled laminated cylindrical panels with geometric imperfection using the isogeometric analysis method. A numerical model based on the first-order shear deformation theory is established to consider geometric imperfection in the nonlinear and buckling analysis of thin-walled shells. An imperfection function is employed to accurately describe the initial imperfection, and an equation based on the effective thermal conductivity of the graphene platelet-strengthened cylindrical panel is presented to determine the temperature distribution. Additionally, a new formula to dictate the volume fraction of graphene platelets is proposed. Through benchmark testing, the isogeometric approach is proven to accurately predict the critical thermal buckling temperature and track the postbuckling behavior. The effect of initial imperfections on the nonlinear postbuckling response behavior is further discussed.
ENGINEERING STRUCTURES
(2023)
Article
Engineering, Marine
Emad Sobhani, Amir R. Masoodi, Amir Reza Ahmadi-Pari
Summary: This paper analyzes the natural frequency of a significant structure, JCCCS, in ocean engineering. The vibrational performance of JCCCS is improved by applying graphene nano-platelet. Various theoretical and numerical methods are employed, and multiple examples are solved to validate the performance of this structure.
Article
Mechanics
Yuewu Wang, Wei Zhang
Summary: In this study, the thermal buckling and postbuckling behaviors of graphene platelet (GPL) reinforced porous nanocomposite beams with temperature-dependent material properties were investigated. The effective properties of nanocomposites were determined using the Halpin-Tsai micromechanics model, extended rule of mixture, and open-cell metal foam model. The governing equations for thermal buckling and postbuckling problems were derived using a high order shear deformation theory with von Karman nonlinearity. To describe the end restraints of the beams, numerically stable admissible functions were constructed using the Gram-Schmidt procedure. The critical buckling temperatures were obtained by solving an eigenvalue equation without geometric nonlinearity, while an iterative methodology was used to find the temperature-dependent thermal postbuckling paths. Extensive numerical study showed that the temperature-dependency of material properties significantly influenced the thermal buckling/postbuckling behaviors of GPL-reinforced porous beams. Dispersing more GPLs on the upper and lower surfaces and fabricating more internal pores near the central portion of the beams improved the thermal instability-resistance capability of composite structures.
COMPOSITE STRUCTURES
(2022)
Article
Engineering, Civil
Qingdong Chai, Yan Qing Wang
Summary: This study investigates the traveling wave vibration characteristics of spinning graphene platelets reinforced metal foam joined conical-cylindrical shells for the first time. The effects of graphene platelets allocation on vibration characteristics are explored, and it is found that allocating more graphene platelets in large-size pore regions is not suitable for increasing traveling wave frequencies. Furthermore, allocating graphene platelets in the conical shell segment can significantly improve traveling wave frequencies compared to the cylindrical shell segment or the whole joined conical-cylindrical shells.
ENGINEERING STRUCTURES
(2022)
Article
Chemistry, Multidisciplinary
Mehran Safarpour, Ali Forooghi, Rossana Dimitri, Francesco Tornabene
Summary: This work investigates the vibration and bending response of FG-GPLRC rectangular plates embedded on different substrates and thermal conditions using theoretical and numerical methods. Results were validated against finite element predictions and showed sensitivity to various factors such as foundation properties and GPL distribution patterns.
APPLIED SCIENCES-BASEL
(2021)
Article
Engineering, Civil
Peng Han, Fangyuan Tian, Hadi Babaei
Summary: A perturbation-based solution is proposed to estimate the thermally induced nonlinear response of graphene platelet (GPL) reinforced composite cylindrical panels. The surrounding medium is modeled using a three-parameter nonlinear elastic foundation. Different distribution patterns and functionally graded (FG) properties are considered for the GPL reinforced composite. The effective material properties of the nanocomposite shell are determined using a mathematical model based on the Halpin-Tsai rule. The semi-analytical solutions, obtained through the perturbation method, provide temperature-deflection relations for simply-supported and clamped-clamped edge conditions, and the effects of various factors on the thermally induced nonlinear response are studied.
Article
Mathematics
Mahmure Avey, Nicholas Fantuzzi, Abdullah H. Sofiyev
Summary: The stability behavior of inhomogeneous nanocomposite cylindrical shells in thermal environments is investigated using the first-order shear deformation theory. Both homogeneous and heterogeneous nanocomposite materials are considered, based on carbon nanotube-reinforced polymer. The critical combined loads for different structures are determined by solving the derived partial differential equations using the Galerkin procedure, and the proposed formulation is tested for reliability against finite element and numerical methods in the literature.
Article
Computer Science, Interdisciplinary Applications
Chang Tao, Ting Dai
Summary: This study focuses on the postbuckling behavior of multilayer functionally graded graphene platelet reinforced composite cylindrical and spherical shell panels under central pinching forces and pressure loadings. Utilizing a higher-order shear deformation theory and von Karman's nonlinear strain-displacement relations, the study establishes governing equations and employs isogeometric analysis and arc-length method for numerical simulations to illustrate the effects of various parameters on the load-deflection curves of the shell panels. The results may serve as valuable references for future studies.
ENGINEERING WITH COMPUTERS
(2022)
Article
Engineering, Civil
R. Ansari, R. Hassani, R. Gholami, H. Rouhi
Summary: In this research, a numerical approach named VDQ-FEM is developed to study the buckling and post-buckling behaviors of variously-shaped plates made of FG-GPLRCs, considering the effect of porosity. Various porosity distribution schemes and GPL dispersion patterns are considered, with the utilization of the closed-cell Gaussian Random field scheme and Halpin-Tsai micromechanical model for material properties computation. The proposed approach efficiently accommodates the continuity of first-order derivatives on common boundaries of elements for the HSDT model. Several numerical examples are provided to analyze the influences of different factors on the buckling and postbuckling characteristics of FG-GPLR porous composite plates.
INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS
(2021)
Article
Mechanics
P. Poungthong, C. Kolitawong, A. J. Giacomin
Summary: This paper analyzes the flow of liquid during the calendering process and provides analytical solutions and methods for calculating flow rate.
Article
Mechanics
Mahdi Salehi, Raheb Gholami, Reza Ansari
Summary: This study presents an analytical solution approach to examine the nonlinear vibration of geometrically imperfect functionally graded porous circular cylindrical shells reinforced with graphene platelets (GPL) surrounded on an elastic foundation. The effective mechanical properties of considered functionally graded graphene platelet-reinforced porous nanocomposites are characterized via a micromechanical model. The nonlinear frequency response curves are obtained with the use of the method of multiple scales.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2023)
Article
Mechanics
Hulun Guo, Krzysztof Kamil Zur, Xu Ouyang
Summary: In this study, the thermal-aerodynamic behaviors of functionally graded graphene nanoplatelets reinforced composite cylindrical panels are theoretically investigated. The established numerical model is verified and the effects of key parameters on the aerothermoelastic responses are comprehensively examined, providing new insights into the stability of graphene platelet reinforced panels under aerodynamic and thermal loadings.
COMPOSITE STRUCTURES
(2023)
Article
Mechanics
Hamed Bagherian, Hamidreza Eipakchi
Summary: In this research, the displacement components of a cylindrical shell under circumferentially varying edge loads and external pressure are analytically determined using the first-order shear deformation theory. Nonlinear von Karman theory defines the kinematics of the problem, while Hooke's law governs the constitutive equations. By applying the virtual work principle, a system of nonlinear nonhomogeneous partial differential equations is derived and solved using perturbation technique and Fourier series method. The presented procedure allows for analysis of shells under continuous or discrete partial loads, and the results are compared with Abaqus finite elements package and existing literature.
Article
Engineering, Civil
Danli Zhang, Yong Wang, Li Li
Summary: This research investigates the natural frequency behavior of functionally graded porous joined hemispherical-cylindrical-hemispherical shell vessels reinforced by graphene platelet (GPLs) for the first time. Different porosity patterns and distribution of GPLs in the metal matrix are considered, and their impact on the natural frequencies is analyzed.
INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS
(2023)
Article
Mechanics
Mahdi Salehi, Raheb Gholami, Reza Ansari
Summary: This study presents an analytical solution approach to examine the nonlinear vibration of geometrically imperfect functionally graded porous circular cylindrical shells reinforced with graphene platelets (GPL) surrounded on an elastic foundation. The effective mechanical properties of considered functionally graded graphene platelet-reinforced porous nanocomposites are characterized via a micromechanical model. The nonlinear frequency response curves are obtained with the use of the method of multiple scales.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2023)
Article
Materials Science, Multidisciplinary
M. Eghbalian, R. Ansari, S. Haghighi
Summary: A two-stage MD-FE modeling method is developed to investigate the influence of functionalized carbon nanotubes on the mechanical properties of polymer materials. MD simulations and FE modeling are used to study the effects of nanotube properties and polymer matrix composition on the strength and stiffness of the materials. In addition, the volume fraction of nanofillers and the percentage of functionalization have significant effects on the material performance.
MECHANICS OF ADVANCED MATERIALS AND STRUCTURES
(2023)
Article
Mechanics
S. Nesarhosseini, R. Ansari, M. Faraji Oskouie, H. Rouhi
Summary: In this paper, the free vibrations of beam-type structures subjected to rapid heating are analyzed using micropolar thermoelasticity. The equations of motion are derived based on the micropolar elasticity theory and the Timoshenko beam theory. The heat equation is modeled using the transient 1D Fourier-type heat conduction equation. The numerical approach utilizes matrix representation and the Newmark algorithm in time domain, as well as generalized differential quadrature and variational differential quadrature techniques in space domain. The effects of thermal shock and geometrical parameters on the thermally induced vibrations are investigated.
Article
Materials Science, Multidisciplinary
Yasin Keramati, Reza Ansari, Mohammad Kazem Hassanzadeh-Aghdam
Summary: This research investigates the effect of adding graphene nano-sheets (GNSs) on the elastic and piezoelectric responses of PZT-7A piezoelectric fiber/polyimide hybrid composites. It develops a nested micromechanical modeling strategy to predict the effective properties of these composites and performs parametric studies to examine the influences of various factors. The results show that the uniform dispersion of GNSs improves the elastic and piezoelectric properties, while agglomeration has a negative effect on the properties.
JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES
(2023)
Article
Chemistry, Physical
M. Eghbalian, R. Ansari, S. Haghighi
Summary: The tensile properties and fracture mechanism of hydroxyl-functionalized silicon carbide nanotubes (O-fSiCNTs) inserted into polymer matrices were studied using molecular dynamics (MD) simulations based on the notion of representative volume elements (RVEs). The incorporation of chemisorbed nanotubes in polymers significantly enhances their mechanical properties. The O-fSiCNTs/PE and O-fSiCNTs/PP demonstrate lower Young's modulus, maximum stress, and strain energy compared to the O-fCNTs/PE and O-fCNTs/PP. The zigzag O-fSiCNTs/polymer exhibit lower bearable maximum strains in response to loads as opposed to the O-fCNTs/polymer.
MOLECULAR SIMULATION
(2023)
Article
Physics, Multidisciplinary
M. Bazdid-Vahdati, R. Ansari, A. Darvizeh
Summary: This paper presents two hyperelastic models for micromorphic hyperelasticity, which are suitable for materials with high dependence on the microdeformation gradient. Two new strain measures based on the microdeformation gradient are introduced and used in the hyperelastic formulation. The developed formulation allows for clear discussion of the dependency on the microdeformation gradient and the formulation of various types of hyperelastic models using the defined strain measures.
EUROPEAN PHYSICAL JOURNAL PLUS
(2023)
Article
Mechanics
Alireza Beheshti, Reza Ansari
Summary: The current work focuses on analyzing the large deformation of shells made of a transversely isotropic material. A higher-order shell model is used to derive strains and extract the stress field of a hyperelastic medium. The weak form is obtained by utilizing the principle of virtual work. A four-node shell element is developed to address locking issues and incorporate transverse shear, membrane, and curvature-thickness locking for a compressible anisotropic medium. Several examples are presented to demonstrate the performance of the proposed element and the effects of anisotropy.
Article
Physics, Multidisciplinary
Y. Gholami, R. Ansari, R. Gholami
Summary: This paper examines the free vibration of single-layered graphene sheets (SLGSs) subjected to compressive in-plane loads and embedded in a Winkler-Pasternak elastic medium. It uses the high-order Cauchy-Born (HCB) method, hyperelastic membrane and second gradient elasticity theory to provide a mathematical formulation. The variational differential quadrature (VDQ) method and Hamilton's principles are applied to obtain a set of discretized governing equations of motion.
EUROPEAN PHYSICAL JOURNAL PLUS
(2023)
Article
Engineering, Mechanical
Babak Ramazani Darvazi, Javad Rezapour, Saeed Rouhi, Raheb Gholami
Summary: In this paper, the nonlinear vortex-induced vibration of electrostatically actuated microbeam is studied based on modified strain gradient theory. The effects of mid-plane stretching, electrostatic actuation, Casimir and intermolecular forces are considered. By applying the Hamilton's principle and using the Galerkin method, the governing equations of motion are derived and the dynamic response and various characteristics are analyzed.
JOURNAL OF VIBRATION ENGINEERING & TECHNOLOGIES
(2023)
Article
Mechanics
R. Ansari, M. Zargar Ershadi, M. Faraji Oskouie, H. Rouhi
Summary: This paper proposes a novel numerical approach to study the large-amplitude geometrically nonlinear vibrations of circular plates made of functionally graded porous materials subjected to hygrothermal loading on an elastic foundation. The modified Voigt's rule of mixture is used to estimate the hygrothermo-mechanical properties of the plates. The effects of hygroscopic stresses and different distribution patterns for porosity are considered. The governing equations for the vibrations are derived based on the first-order shear deformation plate theory and von-Karman geometrical nonlinear relations, and the Winkler-Pasternak model is used to incorporate the effect of the elastic foundation. The problem is solved using the generalized differential quadrature, variational differential quadrature, and Newmark-beta integration methods, and the influences of various parameters on the geometrically nonlinear vibrations are analyzed.
Article
Engineering, Civil
R. Ansari, M. Zargar Ershadi, H. Akbardoost Laskoukalayeh, M. Faraji Oskouie, H. Rouhi
Summary: The nonlinear vibration response of rectangular plates made of functionally graded porous materials induced by hygrothermal loading is investigated in this article using a numerical approach. The effects of elastic foundation and hygroscopic stresses are taken into account, and the temperature-dependent material properties are computed. The temporal evolution of maximum lateral deflection is obtained using the generalized differential quadrature method and Newmark integration method, and the influences of various factors on the vibrations are studied.
INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS
(2023)
Article
Materials Science, Multidisciplinary
Elaheh Kabeh Rahnama, Reza Ansari, Mohammad Kazem Hassanzadeh-Aghdam
Summary: This article investigates the effect of graphene nanoadditives on the fatigue limit of glass fiber-reinforced polymer composites. The study finds that the uniform dispersion of graphene nanosheets can improve the fatigue limit of the composites.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART L-JOURNAL OF MATERIALS-DESIGN AND APPLICATIONS
(2023)
Article
Computer Science, Interdisciplinary Applications
Peyman Aghdasi, Shayesteh Yousefi, Reza Ansari
Summary: This paper uses DFT and FEM to study the elastic, vibrational and buckling properties of monolayer bismuthene. The developed model accurately predicts Young's modulus of the monolayer bismuthene. The influence of the vertical side length on the fundamental natural frequency is negligible, while vibrational characteristics are significantly affected by the horizontal side length.
ENGINEERING COMPUTATIONS
(2023)
Article
Engineering, Civil
R. Ansari, M. Zargar Ershadi, H. Akbardoost Laskoukalayeh, H. Rouhi
Summary: This article develops a numerical approach to study the geometrically nonlinear vibrations of annular sector plates made of functionally graded materials (FGMs) due to cooling shock. The effects of various parameters on the large-amplitude vibrations of annular sector plates are investigated through numerical simulations.
THIN-WALLED STRUCTURES
(2023)
