The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Abdullah H. Sofiyev - One of the best experts on this subject based on the ideXlab platform.
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Large-Amplitude Vibration of functionally graded orthotropic double-curved shallow spherical and hyperbolic paraboloidal shells
International Journal of Pressure Vessels and Piping, 2020Co-Authors: Abdullah H. Sofiyev, F. Turan, Zihni ZerinAbstract:Abstract The purpose of this article is to study the Large Amplitude Vibration behavior of functionally graded orthotropic double-curved shallow shells (FGODCSSs), such as the shallow spherical and hyperbolic paraboloidal shells. After mathematical modeling of the properties of the FG orthotropic material, von-Karman type non-linear basic relations are created, and at the next stage the non-linear equations of motion for double-curved shallow shells are derived. The non-linear basic partial differential equations of FGODCSSs are converted to non-linear ordinary differential equations using the principle of superposition and the Galerkin method. Then non-linear equations are solved by applying the method proposed by Grigolyuk [45] and get the expressions for the frequency-Amplitude relationship and the ratio of the nonlinear frequency to the linear frequency for FGODCSSs. Using these expressions, the results are compared with the results in the literature, and after checking the reliability and accuracy of the proposed formulation, specific numerical calculations are performed. For specific analyzes, the homogenous and FG orthotropic shallow spherical and hyperbolic paraboloidal shells are used, and their Large Amplitude Vibration behaviors are discussed in comparison with each other, and various examples reveal that the influence of heterogeneity is noticeable.
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Large-Amplitude Vibration of the geometrically imperfect FGM truncated conical shell
Journal of Vibration and Control, 2015Co-Authors: Abdullah H. Sofiyev, N KuruogluAbstract:In this study, the Large-Amplitude Vibration of a functionally graded (FG) truncated conical shell with an initial geometric imperfection has been investigated using Large deformation theory with a von Karman–Donnell type of kinematic nonlinearity. The material properties of an FG truncated conical shell are assumed to vary continuously through the thickness. The fundamental relations, the modified Donnell-type nonlinear motion, and compatibility equations of the FG truncated conical shell with an initial geometric imperfection are derived. The relation between nonlinear frequency parameters with the dimensionless Amplitude of imperfect FG truncated conical shells is obtained. Finally, the influences of variations of the initial geometric imperfection, compositional profiles, and shell characteristics on the dimensionless nonlinear frequency parameter and frequency–Amplitude relations are investigated. The present results are compared with the available data for a special case.
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Large-Amplitude Vibration of non-homogeneous orthotropic composite truncated conical shell
Composites Part B: Engineering, 2014Co-Authors: Abdullah H. SofiyevAbstract:Abstract In this study, the Large-Amplitude Vibration of non-homogenous orthotropic composite truncated conical shell is investigated. It is assumed that the Young’s moduli and density of orthotropic materials vary exponentially through the thickness direction. The basic equations of non-homogenous orthotropic truncated conical shell are derived using the finite deflection theory with von Karman–Donnell-type of kinematic non-linearity. Then, foregoing equations are solved using the Superposition principle, Galerkin and Semi-inverse methods and the frequency- Amplitude relationship is found. Finally, carrying out some computations, the effects of non-homogeneity, orthotropy and conical shell characteristics on the nonlinear Vibration characteristics have been studied.
M Rafiee - One of the best experts on this subject based on the ideXlab platform.
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modeling and mechanical analysis of multiscale fiber reinforced graphene composites nonlinear bending thermal post buckling and Large Amplitude Vibration
International Journal of Non-linear Mechanics, 2018Co-Authors: M Rafiee, Fred Nitzsche, Michel R LabrosseAbstract:Abstract In this paper, a mathematical model was developed to predict the effective material properties of graphene nanoplatelets/fiber/polymer multiscale composites (GFPMC). The Large deflection, post-buckling and free nonlinear Vibration of graphene nanoplatelets-reinforced multiscale composite beams were studied through a theoretical study. The governing equations of laminated nanocomposite beams were derived from the Euler–Bernoulli beam theory with von Karman geometric nonlinearity. Halpin–Tsai equations and fiber micromechanics were used in hierarchy to predict the bulk material properties of the multiscale composite. Graphene nanoplatelets (GNPs) were assumed to be uniformly distributed and randomly oriented through the epoxy resin matrix. A semi-analytical approach was used to calculate the Large static deflection and critical buckling temperature of multiscale multifunctional nanocomposite beams. A perturbation scheme was also employed to determine the nonlinear dynamic response and the nonlinear natural frequencies of the beams with clamped–clamped, and hinged–hinged boundary conditions. The effects of weight percentage of graphene nanoplatelets, volume fraction of fibers, and boundary conditions on the static deflection, thermal buckling and post-buckling and linear and nonlinear natural frequencies of the GFPMC beams were investigated in detail. The numerical results showed that the central deflection and natural frequency were significantly improved by a small percentage of GNPs. However, addition of GNPs led to a lower critical buckling temperature.
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nonlinear response of piezoelectric nanocomposite plates Large deflection post buckling and Large Amplitude Vibration
International Journal of Applied Mechanics, 2015Co-Authors: S Mareishi, M Rafiee, K M LiewAbstract:This paper deals with nonlinear response of smart two-phase nanocomposite plates with surface-bonded piezoelectric layers under a combined mechanical, thermal and electrical loading. The governing equations of the carbon nanotube reinforced composite plate are derived based on first order shear deformation plate theory (FSDT) and von Karman geometric nonlinearity. The material properties of the nanocomposite host are assumed to be graded in the thickness direction. The single-walled carbon nanotubes (SWCNTs) are assumed aligned, straight and a uniform layout. The Galerkin method is employed to derive the nonlinear governing equations of the problem. A perturbation scheme is employed to determine the nonlinear Vibration response and the nonlinear natural frequencies of the plates with immovable simply supported boundary conditions. Post-buckling load–deflection and maximum transverse load–deflection relations have been obtained for the plate under consideration. The effects of the applied voltage, temperature change, plate geometry, and the volume fraction and distribution pattern of the SWCNTs on the linear and nonlinear natural frequencies of the smart two-phase composite plates are investigated through a detailed parametric study.
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Large Amplitude Vibration of fractionally damped viscoelastic cnts fiber polymer multiscale composite beams
Composite Structures, 2015Co-Authors: X Q He, M Rafiee, S Mareishi, K M LiewAbstract:An analytical formulation combined with a fractional-order time derivative damping model has been developed to conduct a comprehensive study on the Large Amplitude free and forced Vibration response of carbon nanotubes (CNTs)/fiber/polymer laminated multiscale composite beams. The Caputo fractional derivative of order α is employed to incorporate the viscoelastic material having nonlinear behavior. The governing equations of CNTs/fiber/polymer composite (CNTFPC) beams are coupled second order nonlinear partial FDEs (fractional differential equations) which are derived based on Euler–Bernoulli beam theory and von Karman geometric nonlinearity. Halpin–Tsai equations and fiber micromechanics are used in hierarchy to predict the bulk material properties of the multiscale nanocomposite. The carbon nanotubes are assumed to be uniformly distributed and randomly oriented through the epoxy resin matrix. Discretized by the Galerkin approximation, the perturbation method of multiple time scales is employed to obtain the nonlinear natural frequencies, Amplitude–frequency equation and time history of the beams with hinged–hinged boundary conditions. The effects of the Caputo fractional derivative order, beam geometry, volume fraction of fibers and weight percentage of SWCNTs and MWCNTs on the nonlinear oscillation of the CNTFPC beams are investigated through a detailed parametric study. It is found that nonlinear natural frequencies, Amplitude–frequency relationship and time history are characterized by viscoelastic damping coefficient which are connected with the natural frequency by the exponential relationship with a negative fractional exponent.
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Large Amplitude Vibration of carbon nanotube reinforced functionally graded composite beams with piezoelectric layers
Composite Structures, 2013Co-Authors: M Rafiee, Jie Yang, S KitipornchaiAbstract:Large Amplitude free Vibration of functionally graded carbon nanotube reinforced composite (CNTRC) beams with surface-bonded piezoelectric layers subjected to a temperature change and an applied voltage is studied in this paper. The governing equations of the piezoelectric CNTRC beam are derived based on Euler-Bernoulli beam theory, von Karman geometric nonlinearity and the physical neutral surface concept. Both uniformly distribution (UD) and functionally graded (FG) distribution patterns of the single-walled carbon nanotube (SWCNT) reinforcements are considered. It is assumed that the material properties of the FG-CNTRC beam vary in the thickness direction, and that the SWCNTs are aligned and straight. Galerkin procedure is used to obtain the second order nonlinear ordinary equation in time with cubic nonlinear term. Multiple times scales method is then employed to determine the nonlinear free Vibration characteristics of the beam clamped at both ends. The effects of the applied voltage, temperature change, beam geometry, the volume fraction and distribution pattern of the SWCNTs on the linear and nonlinear frequencies of the piezoelectric CNTRC beams are investigated through a comprehensive parametric study.
K M Liew - One of the best experts on this subject based on the ideXlab platform.
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modeling Large Amplitude Vibration of matrix cracked hybrid laminated plates containing cntr fg layers
Applied Mathematical Modelling, 2018Co-Authors: Z X Lei, L W Zhang, K M LiewAbstract:Abstract This paper presents the mathematical modeling of the nonlinear Vibration behavior of a hybrid laminated plate composed of carbon nanotube reinforced functionally graded (CNTR-FG) layers and conventional fiber reinforced composite (FRC) layers. Three type symmetric distributions of single walled carbon nanotubes (SWCNTs) through the thickness of layers are considered. The cracks are modeled as aligned slit cracks across the ply thickness and transverse to the laminate plane. The distribution of cracks is assumed to be statistically homogeneous corresponding to an average crack density. The obtained partial differential equations are solved by the element-free kp-Ritz method, and the iteration process is dealt with using the linearized updated mode method. Detailed parametric studies are conducted investigate the effects of matrix crack density, CNTs distributions, CNT volume fraction, plate aspect ratio and plate length-to-thickness ratio, boundary conditions and number of layers on the frequency-Amplitude responses of hybrid laminated plates containing CNTR-FG layers.
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nonlinear response of piezoelectric nanocomposite plates Large deflection post buckling and Large Amplitude Vibration
International Journal of Applied Mechanics, 2015Co-Authors: S Mareishi, M Rafiee, K M LiewAbstract:This paper deals with nonlinear response of smart two-phase nanocomposite plates with surface-bonded piezoelectric layers under a combined mechanical, thermal and electrical loading. The governing equations of the carbon nanotube reinforced composite plate are derived based on first order shear deformation plate theory (FSDT) and von Karman geometric nonlinearity. The material properties of the nanocomposite host are assumed to be graded in the thickness direction. The single-walled carbon nanotubes (SWCNTs) are assumed aligned, straight and a uniform layout. The Galerkin method is employed to derive the nonlinear governing equations of the problem. A perturbation scheme is employed to determine the nonlinear Vibration response and the nonlinear natural frequencies of the plates with immovable simply supported boundary conditions. Post-buckling load–deflection and maximum transverse load–deflection relations have been obtained for the plate under consideration. The effects of the applied voltage, temperature change, plate geometry, and the volume fraction and distribution pattern of the SWCNTs on the linear and nonlinear natural frequencies of the smart two-phase composite plates are investigated through a detailed parametric study.
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Large Amplitude Vibration of fractionally damped viscoelastic cnts fiber polymer multiscale composite beams
Composite Structures, 2015Co-Authors: X Q He, M Rafiee, S Mareishi, K M LiewAbstract:An analytical formulation combined with a fractional-order time derivative damping model has been developed to conduct a comprehensive study on the Large Amplitude free and forced Vibration response of carbon nanotubes (CNTs)/fiber/polymer laminated multiscale composite beams. The Caputo fractional derivative of order α is employed to incorporate the viscoelastic material having nonlinear behavior. The governing equations of CNTs/fiber/polymer composite (CNTFPC) beams are coupled second order nonlinear partial FDEs (fractional differential equations) which are derived based on Euler–Bernoulli beam theory and von Karman geometric nonlinearity. Halpin–Tsai equations and fiber micromechanics are used in hierarchy to predict the bulk material properties of the multiscale nanocomposite. The carbon nanotubes are assumed to be uniformly distributed and randomly oriented through the epoxy resin matrix. Discretized by the Galerkin approximation, the perturbation method of multiple time scales is employed to obtain the nonlinear natural frequencies, Amplitude–frequency equation and time history of the beams with hinged–hinged boundary conditions. The effects of the Caputo fractional derivative order, beam geometry, volume fraction of fibers and weight percentage of SWCNTs and MWCNTs on the nonlinear oscillation of the CNTFPC beams are investigated through a detailed parametric study. It is found that nonlinear natural frequencies, Amplitude–frequency relationship and time history are characterized by viscoelastic damping coefficient which are connected with the natural frequency by the exponential relationship with a negative fractional exponent.
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Large Amplitude Vibration of thermo electro mechanically stressed fgm laminated plates
Computer Methods in Applied Mechanics and Engineering, 2003Co-Authors: Jie Yang, S Kitipornchai, K M LiewAbstract:This paper presents a Large Amplitude Vibration analysis of pre-stressed functionally graded material (FGM) laminated plates that are composed of a shear deformable functionally graded layer and two surface-mounted piezoelectric actuator layers. Nonlinear governing equations of motion are derived within the context of Reddy's higher-order shear deformation plate theory to account for transverse shear strain and rotary inertia. Due to the bending and stretching coupling effect, a nonlinear static problem is solved first to determine the initial stress state and pre-Vibration deformations of the plate that is subjected to uniform temperature change, in-plane forces and applied actuator voltage. By adding an incremental dynamic state to the pre-Vibration state, the differential equations that govern the nonlinear Vibration behavior of pre-stressed FGM laminated plates are derived. A semi-analytical method that is based on one-dimensional differential quadrature and Galerkin technique is proposed to predict the Large Amplitude Vibration behavior of the laminated rectangular plates with two opposite clamped edges. Linear Vibration frequencies and nonlinear normalized frequencies are presented in both tabular and graphical forms, showing that the normalized frequency of the FGM laminated plate is very sensitive to Vibration Amplitude, out-of-plane boundary support, temperature change, in-plane compression and the side-to-thickness ratio. The CSCF and CFCF plates even change the inherent hard-spring characteristic to soft-spring behavior at Large Vibration Amplitudes. (C) 2003 Elsevier B.V. All rights reserved.
N Kuruoglu - One of the best experts on this subject based on the ideXlab platform.
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Large-Amplitude Vibration of the geometrically imperfect FGM truncated conical shell
Journal of Vibration and Control, 2015Co-Authors: Abdullah H. Sofiyev, N KuruogluAbstract:In this study, the Large-Amplitude Vibration of a functionally graded (FG) truncated conical shell with an initial geometric imperfection has been investigated using Large deformation theory with a von Karman–Donnell type of kinematic nonlinearity. The material properties of an FG truncated conical shell are assumed to vary continuously through the thickness. The fundamental relations, the modified Donnell-type nonlinear motion, and compatibility equations of the FG truncated conical shell with an initial geometric imperfection are derived. The relation between nonlinear frequency parameters with the dimensionless Amplitude of imperfect FG truncated conical shells is obtained. Finally, the influences of variations of the initial geometric imperfection, compositional profiles, and shell characteristics on the dimensionless nonlinear frequency parameter and frequency–Amplitude relations are investigated. The present results are compared with the available data for a special case.
Jie Yang - One of the best experts on this subject based on the ideXlab platform.
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Large Amplitude Vibration of functionally graded graphene nanocomposite annular plates in thermal environments
Composite Structures, 2020Co-Authors: Ju Zhu, Q Wang, S Kitipornchai, Jie YangAbstract:Abstract This paper investigates the Large Amplitude Vibration of functionally graded nanocomposite multilayer annular plates reinforced with graphene platelets (GPLs) in thermal environments. It is assumed that the GPL concentration varies from layer to layer across the plate thickness but remains constant in each individual GPL-reinforced composite (GPLRC) layer, whose elastic modulus is estimated by the modified Halpin-Tsai micromechanics model. Within the framework of first-order shear deformation theory and von Karman geometric nonlinearity, the governing equations are derived by using the Hamilton’s principle and then solve by the differential quadrature method together with an iterative scheme. Numerical results are presented to show the influences of GPL geometry, distribution pattern and concentration, plate geometry, boundary conditions, as well as temperature rise on the nonlinear Vibration behaviour of functionally graded GPLRC annular plates. It is found that dispersing more GPLs within the outer layers substantially decreases the nonlinear frequency ratio, while the effect of GPL geometry is insignificant.
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Large Amplitude Vibration of carbon nanotube reinforced functionally graded composite beams with piezoelectric layers
Composite Structures, 2013Co-Authors: M Rafiee, Jie Yang, S KitipornchaiAbstract:Large Amplitude free Vibration of functionally graded carbon nanotube reinforced composite (CNTRC) beams with surface-bonded piezoelectric layers subjected to a temperature change and an applied voltage is studied in this paper. The governing equations of the piezoelectric CNTRC beam are derived based on Euler-Bernoulli beam theory, von Karman geometric nonlinearity and the physical neutral surface concept. Both uniformly distribution (UD) and functionally graded (FG) distribution patterns of the single-walled carbon nanotube (SWCNT) reinforcements are considered. It is assumed that the material properties of the FG-CNTRC beam vary in the thickness direction, and that the SWCNTs are aligned and straight. Galerkin procedure is used to obtain the second order nonlinear ordinary equation in time with cubic nonlinear term. Multiple times scales method is then employed to determine the nonlinear free Vibration characteristics of the beam clamped at both ends. The effects of the applied voltage, temperature change, beam geometry, the volume fraction and distribution pattern of the SWCNTs on the linear and nonlinear frequencies of the piezoelectric CNTRC beams are investigated through a comprehensive parametric study.
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Large Amplitude Vibration of thermo electro mechanically stressed fgm laminated plates
Computer Methods in Applied Mechanics and Engineering, 2003Co-Authors: Jie Yang, S Kitipornchai, K M LiewAbstract:This paper presents a Large Amplitude Vibration analysis of pre-stressed functionally graded material (FGM) laminated plates that are composed of a shear deformable functionally graded layer and two surface-mounted piezoelectric actuator layers. Nonlinear governing equations of motion are derived within the context of Reddy's higher-order shear deformation plate theory to account for transverse shear strain and rotary inertia. Due to the bending and stretching coupling effect, a nonlinear static problem is solved first to determine the initial stress state and pre-Vibration deformations of the plate that is subjected to uniform temperature change, in-plane forces and applied actuator voltage. By adding an incremental dynamic state to the pre-Vibration state, the differential equations that govern the nonlinear Vibration behavior of pre-stressed FGM laminated plates are derived. A semi-analytical method that is based on one-dimensional differential quadrature and Galerkin technique is proposed to predict the Large Amplitude Vibration behavior of the laminated rectangular plates with two opposite clamped edges. Linear Vibration frequencies and nonlinear normalized frequencies are presented in both tabular and graphical forms, showing that the normalized frequency of the FGM laminated plate is very sensitive to Vibration Amplitude, out-of-plane boundary support, temperature change, in-plane compression and the side-to-thickness ratio. The CSCF and CFCF plates even change the inherent hard-spring characteristic to soft-spring behavior at Large Vibration Amplitudes. (C) 2003 Elsevier B.V. All rights reserved.
