The Experts below are selected from a list of 18534 Experts worldwide ranked by ideXlab platform
Seung-bok Choi - One of the best experts on this subject based on the ideXlab platform.
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active vibration control of ring stiffened Cylindrical Shell structure using macro fiber composite actuators
Journal of Nanoscience and Nanotechnology, 2014Co-Authors: Jung Woo Sohn, Juncheol Jeon, Seung-bok ChoiAbstract:Vibration control performance of the ring-stiffened Cylindrical Shell structure is experimentally evaluated in this work. In order to achieve high control performance, advanced flexible piezoelectric actuator whose commercial name is Macro-Fiber Composite (MFC) is adapted to the Shell structure. Governing equation is derived by finite element method and dynamic characteristics are investigated from the modal analysis results. Ring-stiffened Cylindrical Shell structure is then manufactured and modal test is conducted to verify modal analysis results. An optimal controller is designed and experimentally realized to the proposed Shell structure system. Vibration control performance is experimentally evaluated in time domain and verified by simulated control results.
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reduction of the radiating sound of a submerged finite Cylindrical Shell structure by active vibration control
Sensors, 2013Co-Authors: Heung Soo Kim, Juncheol Jeon, Jung Woo Sohn, Seung-bok ChoiAbstract:In this work, active vibration control of an underwater Cylindrical Shell structure was investigated, to suppress structural vibration and structure-borne noise in water. Finite element modeling of the submerged Cylindrical Shell structure was developed, and experimentally evaluated. Modal reduction was conducted to obtain the reduced system equation for the active feedback control algorithm. Three Macro Fiber Composites (MFCs) were used as actuators and sensors. One MFC was used as an exciter. The optimum control algorithm was designed based on the reduced system equations. The active control performance was then evaluated using the lab scale underwater Cylindrical Shell structure. Structural vibration and structure-borne noise of the underwater Cylindrical Shell structure were reduced significantly by activating the optimal controller associated with the MFC actuators. The results provide that active vibration control of the underwater structure is a useful means to reduce structure-borne noise in water.
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Vibration Control of a Cylindrical Shell Structure Using Macro Fiber Composite Actuators
Mechanics Based Design of Structures and Machines, 2011Co-Authors: Heung Soo Kim, Jung Woo Sohn, Seung-bok ChoiAbstract:We studied the vibration suppression of an end-capped Cylindrical Shell structure with surface bonded macro fiber composite actuators. The dynamic characteristics of the Cylindrical Shell structure were first analyzed, and then a negative velocity feedback algorithm was applied to suppress the structural vibration at resonance and nonresonance vibration frequencies. The modal mass and stiffness matrix of the smart Cylindrical Shell structure were extracted for the controller design. An active controller was designed to suppress vibration of the smart structure, and the control performance was evaluated in resonance and nonresonance regimes. It was found that structural vibration was reduced by adopting a proper negative velocity feedback control algorithm in both resonance and nonresonance regimes.
Fulei Chu - One of the best experts on this subject based on the ideXlab platform.
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traveling wave vibration of rotating thin circular Cylindrical Shell
Applied Mechanics and Materials, 2012Co-Authors: Yan Qi Liu, Fulei ChuAbstract:In this paper, the vibration characteristics of the rotating thin circular Cylindrical Shell subjected to the radial excitation are presented. Based on the Love’s Shell theory, the governing equation of the rotating thin circular Cylindrical Shell is derived by using the Hamilton’s principle. Then, the amplitude-frequency responses for traveling wave vibration of the circular Cylindrical Shell are investigated. The results indicate that there exists the traveling wave vibration for the rotating thin circular Cylindrical Shell, namely: the forward wave and the backward wave. The effects of the damping and excitation on the amplitude-frequency response are analyzed.
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nonlinear vibrations of rotating thin circular Cylindrical Shell
Nonlinear Dynamics, 2012Co-Authors: Yan Qi Liu, Fulei ChuAbstract:Nonlinear vibrations of thin circular Cylindrical Shells are investigated in this paper. Based on Love thin Shell theory, the governing partial differential equations of motion for the rotating circular Cylindrical Shell are formulated using Hamilton principle. Taking into account the clamped-free boundary conditions, the partial differential system is truncated by using the Galerkin method. Sequentially, the effects of temperature, geometric parameters, circumferential wave number, axial half wave number and rotating speed on the nature frequency of the rotating circular Cylindrical Shell are studied. The dynamic responses of the rotating circular Cylindrical Shell are also investigated in time domain and frequency domain. Then, the effects of nonlinearity, excitation and damping on frequency responses of steady solution are investigated.
Sushil Kale - One of the best experts on this subject based on the ideXlab platform.
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stochastic thermal post buckling response of laminated composite Cylindrical Shell panel with system randomness
International Journal of Applied Mechanics, 2012Co-Authors: Achchhe Lal, B N Singh, Sushil KaleAbstract:The effect of random system properties on thermal post-buckling temperature of laminated composite Cylindrical Shell panel with temperature independent (TID) and dependent (TD) material properties subjected to uniform temperature distribution is examined in this study. System properties such as material properties, thermal expansion coefficients and lamina plate thickness are modeled as independent basic random variables. The basic formulation is based on higher-order shear deformation (HSDT) theory with von-Karman nonlinearity using modified C0 continuty. A direct iterative-based C0 nonlinear finite element method (FEM) combined with Taylor series-based mean-centered first-order perturbation technique (FOPT) developed by the authors for composite plate is extended for Shell panel with reasonable accuracy to compute second-order statistics of post-buckling temperature of Cylindrical Shell panel. Typical numerical results for second order statistics (mean and coefficient of variance) of thermal post-buckling temperature of laminated Cylindrical Shell panel are obtained through numerical examples for various support conditions, amplitude ratios, Shell thickness ratios, aspect ratios, lamination lay-up sequences, curvature to length ratios, types of material properties with the effect of random system parameters. The performance of outlined approach has been validated with those results available in the literatures and independent MCS.
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stochastic post buckling analysis of laminated composite Cylindrical Shell panel subjected to hygrothermomechanical loading
Composite Structures, 2011Co-Authors: Achchhe Lal, B N Singh, Sushil KaleAbstract:Abstract In this paper, the effect of random system properties on the post buckling load of geometrically nonlinear laminated composite Cylindrical Shell panel subjected to hygrothermomechanical loading is investigated. System parameters are assumed as independent random variables. The higher order shear deformation theory and von-Karman nonlinear kinematics are used for basic formulation. The elastic and hygrothermal properties of the composite material are considered to be dependent on temperature and moisture concentration using micromechanical approach. A direct iterative based C0 nonlinear finite element method in conjunction with first-order perturbation technique proposed by present author for the plate is extended for Shell panel subjected to hygrothermomechanical loading to compute the second-order statistics (mean and variances) of laminated composite Cylindrical Shell panel. The effect of random system properties, plate geometry, stacking sequences, support conditions, fiber volume fractions and temperature and moisture distributions on hygrothermomechanical post-buckling load of the laminated Cylindrical Shell panel are presented. The performance of outlined stochastic approach has been validated by comparing the present results with those available in the literature and independent Monte Carlo simulation.
Yan Qi Liu - One of the best experts on this subject based on the ideXlab platform.
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traveling wave vibration of rotating thin circular Cylindrical Shell
Applied Mechanics and Materials, 2012Co-Authors: Yan Qi Liu, Fulei ChuAbstract:In this paper, the vibration characteristics of the rotating thin circular Cylindrical Shell subjected to the radial excitation are presented. Based on the Love’s Shell theory, the governing equation of the rotating thin circular Cylindrical Shell is derived by using the Hamilton’s principle. Then, the amplitude-frequency responses for traveling wave vibration of the circular Cylindrical Shell are investigated. The results indicate that there exists the traveling wave vibration for the rotating thin circular Cylindrical Shell, namely: the forward wave and the backward wave. The effects of the damping and excitation on the amplitude-frequency response are analyzed.
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nonlinear vibrations of rotating thin circular Cylindrical Shell
Nonlinear Dynamics, 2012Co-Authors: Yan Qi Liu, Fulei ChuAbstract:Nonlinear vibrations of thin circular Cylindrical Shells are investigated in this paper. Based on Love thin Shell theory, the governing partial differential equations of motion for the rotating circular Cylindrical Shell are formulated using Hamilton principle. Taking into account the clamped-free boundary conditions, the partial differential system is truncated by using the Galerkin method. Sequentially, the effects of temperature, geometric parameters, circumferential wave number, axial half wave number and rotating speed on the nature frequency of the rotating circular Cylindrical Shell are studied. The dynamic responses of the rotating circular Cylindrical Shell are also investigated in time domain and frequency domain. Then, the effects of nonlinearity, excitation and damping on frequency responses of steady solution are investigated.
Jung Woo Sohn - One of the best experts on this subject based on the ideXlab platform.
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active vibration control of ring stiffened Cylindrical Shell structure using macro fiber composite actuators
Journal of Nanoscience and Nanotechnology, 2014Co-Authors: Jung Woo Sohn, Juncheol Jeon, Seung-bok ChoiAbstract:Vibration control performance of the ring-stiffened Cylindrical Shell structure is experimentally evaluated in this work. In order to achieve high control performance, advanced flexible piezoelectric actuator whose commercial name is Macro-Fiber Composite (MFC) is adapted to the Shell structure. Governing equation is derived by finite element method and dynamic characteristics are investigated from the modal analysis results. Ring-stiffened Cylindrical Shell structure is then manufactured and modal test is conducted to verify modal analysis results. An optimal controller is designed and experimentally realized to the proposed Shell structure system. Vibration control performance is experimentally evaluated in time domain and verified by simulated control results.
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reduction of the radiating sound of a submerged finite Cylindrical Shell structure by active vibration control
Sensors, 2013Co-Authors: Heung Soo Kim, Juncheol Jeon, Jung Woo Sohn, Seung-bok ChoiAbstract:In this work, active vibration control of an underwater Cylindrical Shell structure was investigated, to suppress structural vibration and structure-borne noise in water. Finite element modeling of the submerged Cylindrical Shell structure was developed, and experimentally evaluated. Modal reduction was conducted to obtain the reduced system equation for the active feedback control algorithm. Three Macro Fiber Composites (MFCs) were used as actuators and sensors. One MFC was used as an exciter. The optimum control algorithm was designed based on the reduced system equations. The active control performance was then evaluated using the lab scale underwater Cylindrical Shell structure. Structural vibration and structure-borne noise of the underwater Cylindrical Shell structure were reduced significantly by activating the optimal controller associated with the MFC actuators. The results provide that active vibration control of the underwater structure is a useful means to reduce structure-borne noise in water.
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Vibration Control of a Cylindrical Shell Structure Using Macro Fiber Composite Actuators
Mechanics Based Design of Structures and Machines, 2011Co-Authors: Heung Soo Kim, Jung Woo Sohn, Seung-bok ChoiAbstract:We studied the vibration suppression of an end-capped Cylindrical Shell structure with surface bonded macro fiber composite actuators. The dynamic characteristics of the Cylindrical Shell structure were first analyzed, and then a negative velocity feedback algorithm was applied to suppress the structural vibration at resonance and nonresonance vibration frequencies. The modal mass and stiffness matrix of the smart Cylindrical Shell structure were extracted for the controller design. An active controller was designed to suppress vibration of the smart structure, and the control performance was evaluated in resonance and nonresonance regimes. It was found that structural vibration was reduced by adopting a proper negative velocity feedback control algorithm in both resonance and nonresonance regimes.
