Piezoelectric cantilever bimorph vibrator is the core component of piezoelectric inertial actuators.Piezoelectric cantilever bimorph vibrator with lumped mass at the end is studied,and a dynamic model is constructed b...Piezoelectric cantilever bimorph vibrator is the core component of piezoelectric inertial actuators.Piezoelectric cantilever bimorph vibrator with lumped mass at the end is studied,and a dynamic model is constructed by the proposed method of transforming symmetric electrical signal excitation to equivalent harmonic force excitation.Combining the theory and test,the single-degree-of-freedom damp vibration system consisting of the vibrator is analyzed and the full response is provided.Dynamical system modeling and simulation are conducted by software Matlab/Simulink.The output response of deflection,velocity,acceleration,driving force are solved using the input signal of equivalent harmonic force.Based on the data of theory,simulation and experiments,the deflection of vibrator is analyzed and compared under the excitation of sine wave signal.Result shows that the dynamic deflection results of vibrator from theory,simulation and experiments agree well with each other.The proposed modeling and analysis approaches of the single-degree-of-freedom damp vibration system consisting of the vibrator,have some reference significance for further research of piezoelectric inertial actuators.展开更多
In this paper,an efficient,convenient and explicit method based on the Haar wavelet discretization ap-proach for analyzing the free vibration of the coupled laminated composite elliptical-cylindrical-elliptical shells...In this paper,an efficient,convenient and explicit method based on the Haar wavelet discretization ap-proach for analyzing the free vibration of the coupled laminated composite elliptical-cylindrical-elliptical shells(ECESs)with elastic boundary conditions is presented.Two elliptical double curved shells are cou-pled on both end of cylindrical shell.Based on the first-order shear deformation theory the equations of motion for ECES are derived by means of Hamilton’s principle.The separation of variables is first per-formed;i.e.displacement components and rotations of any point of the ECES are expanded to the Haar wavelet series in the meridian direction and Fourier series in circumferential direction.The constants appearing from the integrating process are determined by boundary conditions,and thus the partial dif-ferential equations are transformed into algebraic equations.By solving the characteristic equation,the natural frequencies and mode shapes of coupled laminated composite ECES are obtained.The present re-sults have been compared with those of the published literature.The comparison results show that this method has high accuracy,high reliability and also a higher convergence rate in attaining the frequencies of the coupled laminated composite ECESs.Then,the effects of the main parameters such as material properties,geometrical parameters,and various boundary conditions,on the vibrational behavior of the coupled ECESs,are investigated.Finally,new free vibration analysis results of the coupled laminated com-posited ECES,which can be used as benchmark data for researchers in this field,are reported through the parameter study.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51175478,51205369)
文摘Piezoelectric cantilever bimorph vibrator is the core component of piezoelectric inertial actuators.Piezoelectric cantilever bimorph vibrator with lumped mass at the end is studied,and a dynamic model is constructed by the proposed method of transforming symmetric electrical signal excitation to equivalent harmonic force excitation.Combining the theory and test,the single-degree-of-freedom damp vibration system consisting of the vibrator is analyzed and the full response is provided.Dynamical system modeling and simulation are conducted by software Matlab/Simulink.The output response of deflection,velocity,acceleration,driving force are solved using the input signal of equivalent harmonic force.Based on the data of theory,simulation and experiments,the deflection of vibrator is analyzed and compared under the excitation of sine wave signal.Result shows that the dynamic deflection results of vibrator from theory,simulation and experiments agree well with each other.The proposed modeling and analysis approaches of the single-degree-of-freedom damp vibration system consisting of the vibrator,have some reference significance for further research of piezoelectric inertial actuators.
文摘In this paper,an efficient,convenient and explicit method based on the Haar wavelet discretization ap-proach for analyzing the free vibration of the coupled laminated composite elliptical-cylindrical-elliptical shells(ECESs)with elastic boundary conditions is presented.Two elliptical double curved shells are cou-pled on both end of cylindrical shell.Based on the first-order shear deformation theory the equations of motion for ECES are derived by means of Hamilton’s principle.The separation of variables is first per-formed;i.e.displacement components and rotations of any point of the ECES are expanded to the Haar wavelet series in the meridian direction and Fourier series in circumferential direction.The constants appearing from the integrating process are determined by boundary conditions,and thus the partial dif-ferential equations are transformed into algebraic equations.By solving the characteristic equation,the natural frequencies and mode shapes of coupled laminated composite ECES are obtained.The present re-sults have been compared with those of the published literature.The comparison results show that this method has high accuracy,high reliability and also a higher convergence rate in attaining the frequencies of the coupled laminated composite ECESs.Then,the effects of the main parameters such as material properties,geometrical parameters,and various boundary conditions,on the vibrational behavior of the coupled ECESs,are investigated.Finally,new free vibration analysis results of the coupled laminated com-posited ECES,which can be used as benchmark data for researchers in this field,are reported through the parameter study.
