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Fabrication of High Acoustic-Electric Efficient Piezoelectric Ceramic Bimorph Element and Pickup in Middle Ear of Cat
KANG Hou-Yong, WU Yong-Zhen, CHI Fang-Lu, GUO Shao-Bo, GAO Na, PAN Tie-Zheng
无机材料学报 , 2010, DOI: 10.3724/sp.j.1077.2010.00691
Abstract: A novel PZT piezoelectric ceramics with high d31 (-480pC/N) and Tc (280℃) was developed to shape a long strip of piezoelectric ceramic bimorph element (PCBE), with 0.3 mm in thickness, 1.0 mm in width and three lengths (3.5, 4.0, 4.5 mm), which were assembled to the cantilever structure anchoring a Preamplifier, and were implanted totally into tympanic cavity of cat ear to analyze their ability of picking up acoustic signal. This study explores that the PCBEs have high efficient acoustic-electric performance. They can pick up 20-20000Hz acoustic signal with an approximate flat frequency curve when they are implanted the tympanic cavity of cat. The maximal output of -13.16 dB Volt p-p value (@1.5kHz, 0dB input) is picked up by the 4.5mm PCBE. This validates that PCBE might be totally implanted into tympanic cavity of cat ear as a piezoelectric microphone.
Study of SH acoustic radiation field excited by a piezoelectric strip
压电条SH声辐射场研究

Zhang Bi-Xing,Wang Cheng-Hao,Bostr?m Anders,
张碧星
,汪承灏,Anders Bostr?m

物理学报 , 2005,
Abstract: A piezoelectric strip of infinite length but with finite width and thickness is placed on top of an isotropic elastic half space. The piezoelectric strip is excited by an electrical signal and the acoustic field is generated. The piezoelectric strip is of type 6mm crystal system oriented along its length direction. The SH wave is studied for the structure of this piezoelectric transducer. At first, the field is expanded as a Fourier series in the piezoelectric strip and as a Fourier integral in the half space. Then, the response of the solution inside the piezoelectric strip and in the half space is obtained by the boundary conditions. The acoustic field distribution is analyzed and compared to that obtained by the traditional method. Finally, the acoustic radiation field at the far field is investigated by the saddle point method and the directional factor is analyzed. It is found that the traditional method is valid only in the case where the product of the frequency with the width of the piezoelectric strip is less than1kHz·m. The stress and displacement in the piezoelectric strip are oscillatory distributions when the frequency increases. The greater the frequency, the greater the difference between the traditional method and the present method.
Finite Element Analysis in Combination with Perfectly Matched Layer to the Numerical Modeling of Acoustic Devices in Piezoelectric Materials  [PDF]
Dbich Karim, Sylvain Ballandras, Thierry Laroche, Karl Wagner, Jean-Michel Brice, Xavier Perois
Applied Mathematics (AM) , 2013, DOI: 10.4236/am.2013.45A008
Abstract:

The characterization of finite length Surface Acoustic Wave (SAW) and Bulk acoustic Wave (BAW) resonators is addressed here. The Finite Element Analysis (FEA) induces artificial wave reflections at the edges of the mesh. In fact, these ones do not contribute in practice to the corresponding experimental response. The Perfectly Matched Layer (PML) method, allows to suppress the boundary reflections. In this work, we first demonstrate the basis of PML adapted to FEA formalism. Next, the results of such a method are depicted allowing a discussion on the behavior of finite acoustic resonators.

Test on an Optimized Cylindrical Non-contact Piezoelectric Actuator  [PDF]
Chen Heng, Chen Chao, Yang Dong, Wang Junshan, Ge Yuyu
- , 2017, DOI: 10.16356/j.1005-1120.2017.01.043
Abstract: An optimization design for the cylindrical non-contact piezoelectric actuator is presented after analyzing the acoustic radiation pressure and acoustic viscous force. By adding the specific microstructure on the rotor to alter the near-field sound effect and maximize the use of high intensity acoustic field induced by the stator to drive the rotor, the rotor speed is increased. The finite element analysis of the acoustic field induced by a variety of rotors with different structures is conducted, A prototype is manufactured, the speed-test system for the actuator is built, and the driving characteristics are measured. The results suggest that the rotation speed of the rotor can reach 4 167 r/min, which demonstrates that the driving characteristics of cylindrical non-contact piezoelectric actuator are successfully improved using the optimization method proposed.
A Novel Approach to a Piezoelectric Sensing Element  [PDF]
M. Martinez,A. Artemev
Journal of Sensors , 2010, DOI: 10.1155/2010/816068
Abstract: Piezoelectric materials have commonly been used in pressure and stress sensors; however, many designs consist of thin plate structures that produce small voltage signals when they are compressed or extended under a pressure field. This study used finite element methods to design a novel piezoelectric pressure sensor with a C-shaped piezoelectric element and determine if the voltage signal obtained during hydrostatic pressure application was enhanced compared to a standard thin plate piezoelectric element. The results of this study demonstrated how small deformations of this C-shaped sensor produced a large electrical signal output. It was also shown that the location of the electrodes for this sensor needs to be carefully chosen and that the electric potential distribution varies depending on the poling of the piezoelectric element. This study indicated that the utilization of piezoelectric materials of different shapes and geometries embedded in a polymer matrix for sensing applications has several advantages over thin plate solid piezoelectric structures. 1. Introduction Pressure gauges of different design types (e.g., U-shaped tube gauges, piston gauges, aneroid gauges, Bourdon tube, or diaphragm gauge [1, 2], optical fiber sensors [3, 4], different electronic sensors) are currently used in different applications. Electronic sensors are convenient because they allow for easy, direct integration into electronic control schemes which can be easily miniaturized and have a short response time when used under dynamic conditions. Electronic pressure sensors can be designed by using different electromechanical or magnetomechanical effects. Electronic sensor types include piezoelectric [5], piezoresistive [6], capacitive, magnetic (inductive), potentiometric, resonant, and surface acoustic wave sensors. In the fields of robotics and orthotics the McKibben actuators have been utilized to mimic the behavior of biological muscles. Son and Goulbourne, 2009 [7] showed how the use of the two electrical parameters capacitance or resistance could be used to measure the large strains/pressure of the actuating device. MEMS based on piezoresistive pressure sensors have also been considered for pressure measurement applications; however they posses low sensitivity and suffer thermal drift [6, 8]. Piezoelectric pressure sensors are commonly used in sensor designs due to their high reliability and robustness, large range of measurable pressure, and low sensitivity to the electro-magnetic field. In traditional piezoelectric pressure sensor designs, the piezoelectric
Dynamic Response of a Thick Piezoelectric Circular Cylindrical Panel: An Exact Solution  [PDF]
Atta Oveisi,Mohammad Gudarzi,Seyyed Mohammad Hasheminejad
Shock and Vibration , 2014, DOI: 10.1155/2014/592165
Abstract: One of the interesting fields that attracted many researchers in recent years is the smart structures. The piezomaterials, because of their ability in converting both mechanical stress and electricity to each other, are very applicable in this field. However, most of the works available used various inexact two-dimensional theories with certain types of simplification, which are inaccurate in some applications such as thick shells while, in some applications due to request of large displacement/stress, thick piezoelectric panel is needed and two-dimensional theories have not enough accuracy. This study investigates the dynamic steady state response and natural frequency of a piezoelectric circular cylindrical panel using exact three-dimensional solutions based on this decomposition technique. In addition, the formulation is written for both simply supported and clamped boundary conditions. Then the natural frequencies, mode shapes, and dynamic steady state response of the piezoelectric circular cylindrical panel in frequency domain are validated with commercial finite element software (ABAQUS) to show the validity of the mathematical formulation and the results will be compared, finally. 1. Introduction Piezoelectric materials have been extensively used as transducers and sensors due to their intrinsic direct and converse piezoelectric effects that take place between electric field and mechanical deformation. An important geometry in applied engineering problems is circular cylindrical panel because of its widespread application in actual structures such as aircraft wings, submarines, missiles, vessels, and high pressure cylindrical containers. The application of piezomaterial structures in this field is mainly concentrated on vibration suppression and acoustic noise reduction. Because of practical applications, piezoelectric circular cylindrical shells have attracted a considerable amount of research interests. Haskins and Walsh analyzed the free vibration of piezoelectric cylindrical shells with radially polarized transverse isotropy [1]; Martin investigated the vibration of longitudinally polarized piezoelectric cylindrical tubes and pointed out the limitations of the assumption [2]. Drumheller and Kalnins presented a coupled theory for the vibration of piezoceramic shells of revolution and analyzed the free axisymmetrical vibration of a circular cylindrical shell [3]. Burt simplified the circular cylinder to a two-dimensional model and then investigated the voltage response of radially polarized ceramic [4]. Tzou and Zhong gave a linear theory of
极端环境下的惯性测量传感器件与系统
Piezoelectric-Acoustic-Thermal Calculation Model of Low-Frequency Sonophoresis Transdermal Drug Delivery System
 [PDF]

薛晨阳,钱坤,刘俊,唐军,石云波,李杰
- , 2015, DOI: 10.16450/j.cnki.issn.1004-6801.2015.06.001
Abstract: 面向惯性传感与测量系统在超高过载、超高转速等极端应用环境下,介绍了几种典型的瞬态高量程与大动态范围条件下的惯性传感与测量系统技术。重点分析和讨论了极端环境下的超量程与大动态测试所需的特种传感方法与微纳集成制造技术,结合特殊的封装防护与系统集成方法,实现外部恶劣环境影响因子的衰减,以及新型的高过载、高旋运动载体惯性参数的传感与测量。
In order to analyze the thermal problem from ultrasonic cavitations in the low-frequency sonophoresis process for transdermal drug delivery, this paper establishes a stimulation model for piezoelectric-sound-thermal coupling fields in sonophoresis based on COMSOL Multiphysics software, which utilizes piezoelectric, heat transfer and acoustic balance equations. Further, the temperature field distribution and maximum surface temperature curve changing with time are acquired from both the finite element method (FEM) and thermal imaging system with input electrical power of 5.5 W and driving frequency of 21 kHz. The simulation and calculation results show that the temperature field distribution and maximum surface temperature curve of the FEM calculations are consistent with those of the experimental results in both the alone-heating ultrasonic transducer and low-frequency sonophoresis system with a Franz diffusion cell in the air. In the low-frequency sonophoresis process, sharp sound attenuation caused by ultrasonic cavitations in the liquid contributes to fast heating, due to the transformation of acoustic energy into thermal energy. In the thermal imaging experiments, the highest surface temperature in the sonophoresis system reached 40℃ in 15 min. According to the simulation results, the maximum temperature of the whole system reached 41.3℃, which meets the temperature safety requirements of 42℃ or lower for low-frequency sonophoresis transdermal drug delivery. Calculated and experimental results demonstrate that by predicting the temperature distribution, the piezoelectric-acoustic-thermal coupling calculation model is beneficial for the design of ultrasonic radiation time control, the determination of structure size, and the optimization of the material parameters of the ultrasonic transducer, and thereby lays a theoretical basis for the multiple applications of different sonophoresis conditions.
Energy Harvesting with Piezoelectric Element Using Vibroacoustic Coupling Phenomenon  [PDF]
Hiroyuki Moriyama,Hirotarou Tsuchiya,Yasuo Oshinoya
Advances in Acoustics and Vibration , 2013, DOI: 10.1155/2013/126035
Abstract: This paper describes the vibroacoustic coupling between the structural vibrations and internal sound fields of thin structures. In this study, a cylindrical structure with thin end plates is subjected to the harmonic point force at one end plate or both end plates, and a natural frequency of the end plates is selected as the forcing frequency. The resulting vibroacoustic coupling is then analyzed theoretically and experimentally by considering the dynamic behavior of the plates and the acoustic characteristics of the internal sound field as a function of the cylinder length. The length and phase difference between the plate vibrations, which maximize the sound pressure level inside the cavity, are clarified theoretically. The theoretical results are validated experimentally through an excitation experiment using an experimental apparatus that emulates the analytical model. Moreover, the electricity generation experiment verifies that sufficient vibroacoustic coupling can be created for the adopted electricity generating system to be effective as an electric energy-harvesting device. 1. Introduction Recently, scavenging ambient vibration energy and converting it into usable electric energy via piezoelectric materials have attracted considerable attention [1]. Typical energy harvesters adopt a simple cantilever configuration to generate electric energy via piezoelectric materials, which are attached to or embedded in vibrational elements. High-amplitude excitations reduce the fatigue life of these harvesters. Thus, placing appropriate constraints on the amplitudes is one of significant ways to improve the performance of harvesters. A cantilever beam, whose deflection was constrained by a bump stop, was modeled. The effect of electromechanical coupling was estimated in a parametric study, where the placement of the bump stop and the gap between the beam and stop were chosen as parameters [2]. Acoustic energy as well as vibration energy to be harvested sufficiently fills our working environment. Thermoacoustic engines that exploit the inherently efficient Stirling cycle and are designed on the basis of a simple acoustic apparatus with no moving parts have been regarded as the representative means for harvesting acoustic energy [3]. As an example application, electricity generation using resonance phenomena in a thermoacoustic engine was investigated with aim of harvesting the work done in the engine. The acoustic energy spent on electricity generation was harvested from a resonance tube branching out of the engine, and the appropriate position of the
An Overview on Piezoelectric Power Generation System for Electricity Generation  [PDF]
Xiaoming Sun
Journal of Power and Energy Engineering (JPEE) , 2017, DOI: 10.4236/jpee.2017.52002
Abstract: Coal, petroleum and natural gas will still be the basis of economic development for a long time. However, with a rapider consumption speed, these fossil fuels will be exhausted in the near future. In addition, the usage of these fossil fuels can also cause environmental pollution and greenhouse effect. To deal with energy security and environmental crisis, it is wise to work towards three directions: energy saving and emission reduction, energy recovery, exploration of new renewable energy. Currently, the electricity generation technology using piezoelectric material to recover the compressional or vibrational energy begins to draw attention. However, most of the researches are devoted to designing small self-powered devices. This paper presents an overview of the feasibility of piezoelectric power generation system for electric power system, in which the fundamentals of piezoelectric power generation and the feasible structure of the system are discussed.
Development of a Multi-Channel Piezoelectric Acoustic Sensor Based on an Artificial Basilar Membrane  [PDF]
Youngdo Jung,Jun-Hyuk Kwak,Young Hwa Lee,Wan Doo Kim,Shin Hur
Sensors , 2014, DOI: 10.3390/s140100117
Abstract: In this research, we have developed a multi-channel piezoelectric acoustic sensor (McPAS) that mimics the function of the natural basilar membrane capable of separating incoming acoustic signals mechanically by their frequency and generating corresponding electrical signals. The McPAS operates without an external energy source and signal processing unit with a vibrating piezoelectric thin film membrane. The shape of the vibrating membrane was chosen to be trapezoidal such that different locations of membrane have different local resonance frequencies. The length of the membrane is 28 mm and the width of the membrane varies from 1 mm to 8 mm. Multiphysics finite element analysis (FEA) was carried out to predict and design the mechanical behaviors and piezoelectric response of the McPAS model. The designed McPAS was fabricated with a MEMS fabrication process based on the simulated results. The fabricated device was tested with a mouth simulator to measure its mechanical and piezoelectrical frequency response with a laser Doppler vibrometer and acoustic signal analyzer. The experimental results show that the as fabricated McPAS can successfully separate incoming acoustic signals within the 2.5 kHz–13.5 kHz range and the maximum electrical signal output upon acoustic signal input of 94 dBSPL was 6.33 mVpp. The performance of the fabricated McPAS coincided well with the designed parameters.
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