The energy relationships among all the elements, by which the magnetostrictive transducers are manufactured, in Finite Element Method (FEM) are analyzed, then the expres- sions of FEM dynamics equations and performanc...The energy relationships among all the elements, by which the magnetostrictive transducers are manufactured, in Finite Element Method (FEM) are analyzed, then the expres- sions of FEM dynamics equations and performances formulas for magnetostrictive transducers are derived. The vibrating modes of the class VII transducer and its shell vibration are calcu- lated theoretically and the results point out that there is a breathing mode and if the transducer works at this mode, the transducer will vibrate with a greater volume speed and source level.展开更多
A flextensional transducer with an Omega shape and its algorithmic method of the resonant frequency and the shape functions are suggested. The Omega transducer is separated into four parts treated respectively as a th...A flextensional transducer with an Omega shape and its algorithmic method of the resonant frequency and the shape functions are suggested. The Omega transducer is separated into four parts treated respectively as a thin shell of revolution and the theories of thin shells of revolution and piezoelectricity are used to obtain the energy functional of each part so that the sum of the energy functionals of the four parts is the energy functional of the whole Omega transducer. By substituting the shape functions with undetermined coefi3cients and the geo- metrical boundary conditions into the energy functional of the Omega transducer, the resonant frequency of the Omega transducer is firstly determined with the Rayleigh-Ritz method. With the gotten resonant frequency, the constant coefficients of the shape functions are following solved through the Rayleigh-Ritz partial differential equations and the geometrical boundary condition equations. The solving method of the resonant frequency and the shape functions is also extended to the cymbal transducer. Such an analytical method is verified to be feasible by the results of the finite element analysis and experiments. The research indicates that （1） The radial vibration of the piezoelectric ceramic is in phase with the longitudinal vibration of the top of metal cap, and it cut down the reversed phase component in the sound field. The Omega transducer can be a low frequency transducer. （2） The determination method of the resonant frequency and the shape functions give a solution to the optimum designs of the Omega transducer and the cymbal transducer. （3） The determination method of the resonant fi＇equency and the shape functions can also be used in other flextensional transducers or other structures which are composed of thin shells of revolution, so it is universal.展开更多
An innovative design of a 'Fish-mouth' flextensional transducer is proposed, it is utilized an elliptical shell with variable height. The special shell is provided with amplitude amplification and weighted he...An innovative design of a 'Fish-mouth' flextensional transducer is proposed, it is utilized an elliptical shell with variable height. The special shell is provided with amplitude amplification and weighted height amplification effect that is called 'double-amplification' effect. A prototype of the Terfenol-D 'Fish-mouth' flextensional transducer is developed. Theoretical analysis and experiments in lake are showed that the 'Fish-mouth' flextensional transducer has lower resonant frequency: about 1.1 kHz, wider frequency band: Q factor for - 3 dB bandwidth less than 3, transmitting current response level: 182 dB. A free-flooded cavity with compliant material is used to achieve depth capability.展开更多
Vibrating modes of the manufactured flextensional transducer and its shell are experimentally investigated. The result are consistent with the theoretical calculations. The acoustical performances for the transducer a...Vibrating modes of the manufactured flextensional transducer and its shell are experimentally investigated. The result are consistent with the theoretical calculations. The acoustical performances for the transducer are measured: resonance frequency is 1.16 kHz in the underwater, bandwidth is 680 Hz, mechanical quality factor is 1.71, transmitting current response is 186.1 dB, electromechanical efficiency is 13.1%.展开更多
基金the Scientific Fund of Shaanxi Province and the Youth Scientific Fund ofShaanxi Normal University
文摘The energy relationships among all the elements, by which the magnetostrictive transducers are manufactured, in Finite Element Method (FEM) are analyzed, then the expres- sions of FEM dynamics equations and performances formulas for magnetostrictive transducers are derived. The vibrating modes of the class VII transducer and its shell vibration are calcu- lated theoretically and the results point out that there is a breathing mode and if the transducer works at this mode, the transducer will vibrate with a greater volume speed and source level.
基金supported by the Young Scientists Ftmd of the National Natural Science Foundation of China(51005241)the Postdoctoral Science and Technology Activities Preferred Financing Project in Hubei Province
文摘A flextensional transducer with an Omega shape and its algorithmic method of the resonant frequency and the shape functions are suggested. The Omega transducer is separated into four parts treated respectively as a thin shell of revolution and the theories of thin shells of revolution and piezoelectricity are used to obtain the energy functional of each part so that the sum of the energy functionals of the four parts is the energy functional of the whole Omega transducer. By substituting the shape functions with undetermined coefi3cients and the geo- metrical boundary conditions into the energy functional of the Omega transducer, the resonant frequency of the Omega transducer is firstly determined with the Rayleigh-Ritz method. With the gotten resonant frequency, the constant coefficients of the shape functions are following solved through the Rayleigh-Ritz partial differential equations and the geometrical boundary condition equations. The solving method of the resonant frequency and the shape functions is also extended to the cymbal transducer. Such an analytical method is verified to be feasible by the results of the finite element analysis and experiments. The research indicates that （1） The radial vibration of the piezoelectric ceramic is in phase with the longitudinal vibration of the top of metal cap, and it cut down the reversed phase component in the sound field. The Omega transducer can be a low frequency transducer. （2） The determination method of the resonant frequency and the shape functions give a solution to the optimum designs of the Omega transducer and the cymbal transducer. （3） The determination method of the resonant fi＇equency and the shape functions can also be used in other flextensional transducers or other structures which are composed of thin shells of revolution, so it is universal.
文摘An innovative design of a 'Fish-mouth' flextensional transducer is proposed, it is utilized an elliptical shell with variable height. The special shell is provided with amplitude amplification and weighted height amplification effect that is called 'double-amplification' effect. A prototype of the Terfenol-D 'Fish-mouth' flextensional transducer is developed. Theoretical analysis and experiments in lake are showed that the 'Fish-mouth' flextensional transducer has lower resonant frequency: about 1.1 kHz, wider frequency band: Q factor for - 3 dB bandwidth less than 3, transmitting current response level: 182 dB. A free-flooded cavity with compliant material is used to achieve depth capability.
基金the Scientific fund of Shaanxi Province and the Youth Scientific fund of Shaanxi Normal University.
文摘Vibrating modes of the manufactured flextensional transducer and its shell are experimentally investigated. The result are consistent with the theoretical calculations. The acoustical performances for the transducer are measured: resonance frequency is 1.16 kHz in the underwater, bandwidth is 680 Hz, mechanical quality factor is 1.71, transmitting current response is 186.1 dB, electromechanical efficiency is 13.1%.
