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压电水声换能器宽带匹配特性研究
Research on broadband matching performance of piezoelectric underwater acoustic transducer
 [PDF]

周瑜,涂其捷,杨荣耀,唐建生
- , 2018, DOI: 10.16300/j.cnki.1000-3630.2018.03.017
Abstract: 采用等效电路变换和多物理场有限元仿真计算进行压电水声换能器宽带匹配特性研究,得出不同匹配电路下的换能器电声性能的变化规律,合理选择电感电容值和串并联方式进行调谐匹配实现双峰谐振,一方面提高换能器的工作带宽,另一方面提高工作频率范围内的发送电压响应值并减小工作频带内响应值的起伏,依照仿真数据设计制作了一款球形换能器,采用串联电感进行调谐匹配,并测试调谐匹配前后的水中电声性能,对比匹配前后换能器性能的差异。结果表明,测试结果和仿真计算吻合,运用多物理场仿真计算手段对于预测分析水声换能器电声性能具有较好的指导意义。
In this paper the equivalent circuit transformation and multi-physics field finite element simulation is used to research the characteristics of piezoelectric acoustic transducer with broadband matching performance, and the variation of electro-acoustic characteristics of the transducer with different matching circuits is obtained. By reasonably choosing the values of inductance and capacitance as well as the way of series-parallel connection, the double-humped response is achieved to broaden the working frequency range, and to improve the transmitting voltage response (TVR) and reduce the fluctuation in the working frequency range. According to the simulation data, a transducer is designed with the tuned matching using series inductance. The performance difference of the transducer before and after matching is tested. The test results are in agreement with the simulation calculation. It means that the multi-physics field simulation calculation has good guiding significance for predicting and analyzing the performance of underwater acoustic transducer.
Design of a High Frequency Driving Circuit of Surface Acoustic Wave Transducer
Guan Zhao
Open Access Library Journal (OALib Journal) , 2018, DOI: 10.4236/oalib.1104737
Abstract:
In this paper, a high frequency driving circuit of surface acoustic wave transducer has been designed to separate oil from oil/water mixed droplet. The transmission frequency of the surface acoustic wave transducer driving circuit can be up to 1 MHz. The transmit frequency of conventional ultrasonic driving circuit is mostly 40 kHz. However, the high transmit frequency driving circuit presents a good stability and accuracy. By establishing the surface acoustic wave driving circuit model, the actual circuit and debugging verification, the driving circuit can excite the frequency signal required for the experiment. Thus, the surface acoustic wave driving circuit could provide necessary technical support for application in other fields.
Voltage Generated Characteristics of Piezoelectric Ceramics Cymbal Transducer  [PDF]
Long Wu, Ming-Cheng Chure, King-Kung Wu, Chia-Cheng Tung
Journal of Materials Science and Chemical Engineering (MSCE) , 2014, DOI: 10.4236/msce.2014.210005
Abstract:

In this study the relation between the generated open circuit output voltages of the piezoelectric ceramics Cymbal transducers with applied impact mechanical energy is studied. The output voltages of piezoelectric ceramics Cymbal transducers are increased with the increasing of the applied mechanical energy. Under the same impact mechanical energy, the generated open circuit output voltages of the piezoelectric ceramics Cymbal transducer is much higher than that of uncapped piezoelectric ceramics disk alone. The generated open circuit output voltages of the piezoelectric ceramics Cymbal transducer depend on the geometry parameters and the metal thickness of end-cap. The generated open circuit voltage of piezoelectric ceramics Cymbal transducer with thick metal thickness is small than that with thin metal thickness.

The Analyzing of Ultrasound Propagation Wawes through a Piezoelectric Transducer in Function of Acoustic Charge  [PDF]
Grigore Liviu Odobescu
Analele Universit??ii Eftimie Murgu Re?i?a. Fascicula de Inginerie , 2010,
Abstract: The nature of acoustic charge, which works with an electronic generator to generate high intensity ultra-acoustic field is very various in function of application used [2]. The values of elements from equivalent scheme may be to vary in time in function of technologic process [3]. This fact determines the variation of accord frequencies and value of acoustic charge. In this manner the efficiency can be modified in time if it no take measures to minimize these influences of complex impedance that works with electronic generator [4]. In this paper it is presented a method to analysis the influence of variation of acoustic charge and to minimize this influences for to assure an optimum operation of electronic generator, it is presented a program to calculate the power variation in function of acoustic charge and to chart the diagram of this variation. It is presented the experimental results obtained with the theory presented.
A New Method to Improve the Simulation Of Piezoelectric Transducer Using PSPICE And Genetic Algorithms
Dr. M . M. Elgazzar
International Journal on Computer Science and Engineering , 2011,
Abstract: Piezoelectric transducer (SAW devices) is a very important device in industry but it is very difficult to simulate it using any circuit-simulation program. This paper proposes a practical method to simulatethe Mason’s model of piezoelectric transducer directly with no approximation for different values of the model’s components using PSPICE. The paper also improves the simulated circuit component valuesusing a Genetic Algorithms module. This optimization of the simulated circuit parameters minimizes the difference between the real output behavior of the piezoelectric transducer and the output of thesimulated circuit using PSPICE. The paper also contrasts the new method with two other methods that simulate the Mason’s model of the piezoelectric transducer.
Circuit-field coupled finite element analysis method for an electromagnetic acoustic transducer under pulsed voltage excitation

Hao Kuan-Sheng,Huang Song-Ling,Zhao Wei,Wang Shen,

中国物理 B , 2011,
Abstract: This paper presents an analytical method for electromagnetic acoustic transducers (EMATs) under voltage excitation and considers the non-uniform distribution of the biased magnetic field. A complete model of EMATs including the non-uniform biased magnetic field, a pulsed eddy current field and the acoustic field is built up. The pulsed voltage excitation is transformed to the frequency domain by fast Fourier transformation (FFT). In terms of the time harmonic field equations of the EMAT system, the impedances of the coils under different frequencies are calculated according to the circuit-field coupling method and Poynting's theorem. Then the currents under different frequencies are calculated according to Ohm's law and the pulsed current excitation is obtained by inverse fast Fourier transformation (IFFT). Lastly, the sequentially coupled finite element method (FEM) is used to calculate the Lorentz force in the EMATs under the current excitation. An actual EMAT with a two-layer two-bundle printed circuit board (PCB) coil, a rectangular permanent magnet and an aluminium specimen is analysed. The coil impedances and the pulsed current are calculated and compared with the experimental results. Their agreement verified the validity of the proposed method. Furthermore, the influences of lift-off distances and the non-uniform static magnetic field on the Lorentz force under pulsed voltage excitation are studied.
Annular interdigital transducer focuses piezoelectric surface waves to a single point  [PDF]
Vincent Laude,Davy Gérard,Naima Khelfaoui,Carlos F. Jerez-Hanckes,Sarah Benchabane,Abdelkrim Khelif
Physics , 2007, DOI: 10.1063/1.2891055
Abstract: We propose and demonstrate experimentally the concept of the annular interdigital transducer that focuses acoustic waves on the surface of a piezoelectric material to a single, diffraction-limited, spot. The shape of the transducing fingers follows the wave surface. Experiments conducted on lithium niobate substrates evidence that the generated surface waves converge to the center of the transducer, producing a spot that shows a large concentration of acoustic energy. This concept is of practical significance to design new intense microacoustic sources, for instance for enhanced acouto-optical interactions.
Shear Wave Field Radiated by an Electromagnetic Acoustic Transducer
WU Di,LI Ming-Xuan,WANG Xiao-Min,
吴迪
,李明轩,王小民

中国物理快报 , 2006,
Abstract: The horizontally polarized ultrasonic shear wave field emitted by an electromagnetic acoustic transducer (EMAT) is studied by the surface force distribution on the EMAT approximately described as an inhomogeneous horizontal shear force. The shear wave directivity pattern is plotted by numerical calculations based on our strictly analytic solutions of the wave field we presented previously. An experimental system of EMAT generation and piezoelectric transducer reception is set up to check the predictions of the theoretical wave field by measuring the ultrasonic signals through aluminium block. The directivity pattern of the wave field obtained from the experimental results conforms the theoretical prediction, which lays a foundation for engineering applications of EMATs.
A Four-Quadrant PVDF Transducer for Surface Acoustic Wave Detection  [PDF]
Zimo Lu,Dante J. Dorantes-Gonzalez,Kun Chen,Fei Yang,Baoyin Jin,Yanning Li,Zhi Chen,Xiaotang Hu
Sensors , 2012, DOI: 10.3390/s120810500
Abstract: In this paper, a polyvinylidene fluoride (PVDF) piezoelectric transducer was developed to detect laser-induced surface acoustic waves in a SiO2-thin film–Si-substrate structure. In order to solve the problems related to, firstly, the position of the probe, and secondly, the fact that signals at different points cannot be detected simultaneously during the detection process, a four-quadrant surface acoustic wave PVDF transducer was designed and constructed for the purpose of detecting surface acoustic waves excited by a pulse laser line source. The experimental results of the four-quadrant piezoelectric detection in comparison with the commercial nanoindentation technology were consistent, the relative error is 0.56%, and the system eliminates the piezoelectric surface wave detection direction deviation errors, improves the accuracy of the testing system by 1.30%, achieving the acquisition at the same time at different testing positions of the sample.
A thermal insulation method for a piezoelectric transducer
Song Wu,Hong Chen,JiaHua Gu,HongRu Yu
Chinese Science Bulletin , 2007, DOI: 10.1007/s11434-007-0366-y
Abstract: This study deals with the sources of signal distortion of a piezoelectric transducer heated by measured gas flow. These signal distortions originate from both unloading of preload on a piezocrystal because of expansion of a diaphragm in the test apparatus and the pyroelectric effect of a heated piezoelectric crystal. A plastic film on the diaphragm of the transducer can effectively insulate the diaphragm and the piezocrystal within transducer from heating by gas flow, eliminating the sources of distortion. A method for evaluating the thickness of the film is proposed.
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