IEEE Ultrasonics Symposium, 2005.最新文献_第10页

A comparison of piezoelectric and electrostatic electromechanical coupling for ultrasonic transduction and power generation 压电与静电机电耦合用于超声转导与发电的比较

IEEE Ultrasonics Symposium, 2005. Pub Date : 2005-09-18 DOI: 10.1109/ULTSYM.2005.1603008

M.J. Anderson, J. Cho, C. Richards, D. Bahr, R. Richards

{"title":"A comparison of piezoelectric and electrostatic electromechanical coupling for ultrasonic transduction and power generation","authors":"M.J. Anderson, J. Cho, C. Richards, D. Bahr, R. Richards","doi":"10.1109/ULTSYM.2005.1603008","DOIUrl":"https://doi.org/10.1109/ULTSYM.2005.1603008","url":null,"abstract":"Electrostatic and piezoelectric electromechanical coupling are employed in miniature devices to produce ultrasonic waves or generate power. It has been pointed out in the technical literature that in principle electrostatic devices can be designed to have an electromechanical coupling factor of nearly 100%, while it is thought that the upper limit for piezoelectric devices is significantly smaller. We have recently developed a closed-form model of a thin-film piezoelectric device to predict the performance of membrane piezoelectric energy converters. The model was used to identify several key design and process parameters that have a substantial effect on electromechanical coupling. This model is general enough to allow a comparison of the two technologies, electrostatics and piezoelectrics, at a lower level of detail. In this paper, the model is used to compare the components of the electromechanical coupling factor; capacitance, stiffness, and actuation force, for the two energy conversion technologies. The comparison shows that the capacitance and actuation force coefficient are drastically different for the two technologies, and are controlled by fundamental material properties and device geometries. Consequences of the differences for the design of ultrasonic transducers and power generation devices are discussed.","PeriodicalId":302030,"journal":{"name":"IEEE Ultrasonics Symposium, 2005.","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127201560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Determination of velocity vector angles using the directional cross-correlation method 用方向互相关法确定速度矢量角

IEEE Ultrasonics Symposium, 2005. Pub Date : 2005-09-18 DOI: 10.1109/ULTSYM.2005.1603101

J. Kortbek, J. Jensen

{"title":"Determination of velocity vector angles using the directional cross-correlation method","authors":"J. Kortbek, J. Jensen","doi":"10.1109/ULTSYM.2005.1603101","DOIUrl":"https://doi.org/10.1109/ULTSYM.2005.1603101","url":null,"abstract":"A method for determining both velocity magnitude and angle in any direction is suggested. The method uses focusing along the velocity direction and cross-correlation for finding the correct velocity magnitude. The angle is found from beamforming directional signals in a number of directions and then select the angle with the highest normalized correlation between directional signals. The approach is investigated using Field II simulations and data from the experimental ultrasound scanner RASMUS and with a parabolic flow having a peak velocity of 0.3 m/s. A 7 MHz linear array transducer is used with a normal transmission of a focused ultrasound field. The velocity profile estimates from simulations have relative mean standard deviations between 0.7% and 7.7% for flow between 45 ◦ and 90 ◦ . The angle estimation performance is highly dependent on the choice of the time ktprf · Tprf (correlation-time) between signals to correlate, and a proper choice varies with flow angle and flow velocity. One performance example is given with a fixed value of ktprf for all flow angles. The angle estimation on measured data for flow at 60 ◦ to 90 ◦ , yields a probability of valid estimates between 68% and 98% and with standard deviations between 1 ◦ and 4 ◦ . The optimal value of ktprf for each flow angle is found from a parameter study to reveal the potential of the method and with these values the performance on simulated data yields angle estimates with no outlier estimates and with standard deviations below 2 ◦ .","PeriodicalId":302030,"journal":{"name":"IEEE Ultrasonics Symposium, 2005.","volume":"253 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127360852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Polyimide backed 40-MHz PVDF transducers 聚酰亚胺支持40兆赫PVDF传感器

IEEE Ultrasonics Symposium, 2005. Pub Date : 2005-09-18 DOI: 10.1109/ULTSYM.2005.1602810

J. Ketterling, O. Aristizábal, D. Turnbull

引用次数: 5

Strain measurements on carbon-epoxy composites by lamb waves piezopolymer interdigital transducers 用lamb波压电聚合物数字间换能器测量碳环氧复合材料的应变

IEEE Ultrasonics Symposium, 2005. Pub Date : 2005-09-18 DOI: 10.1109/ULTSYM.2005.1602879

A. Bulletti, L. Capineri, L. Masotti, O. Occhiolini, E. Rosi

引用次数: 1

Analyses of surface acoustic wave propagation in phononic crystal waveguides using FDTD method 利用时域有限差分法分析声子晶体波导中表面声波的传播

IEEE Ultrasonics Symposium, 2005. Pub Date : 2005-09-18 DOI: 10.1109/ULTSYM.2005.1602799

Jia-Hong Sun, Tsung-Tsong Wu

引用次数: 7

Optical label recognition in spectral and time domains with collinear acoustooptic devices for photonic router 光子路由器用共线声光器件的光谱和时域光学标签识别

IEEE Ultrasonics Symposium, 2005. Pub Date : 2005-09-18 DOI: 10.1109/ULTSYM.2005.1602830

N. Goto, Y. Miyazaki

引用次数: 0

Electro-acoustical constants and Rayleigh SAW propagation characteristics of rare-earth calcium oxoborate single crystals 稀土氧化硼酸钙单晶的电声常数和瑞利声表面波传播特性

IEEE Ultrasonics Symposium, 2005. Pub Date : 2005-09-18 DOI: 10.1109/ULTSYM.2005.1603004

H. Shimizu, Ayako Kondo, M. Nishida, H. Takeda, T. Nishida, Tadashi Nara

{"title":"Electro-acoustical constants and Rayleigh SAW propagation characteristics of rare-earth calcium oxoborate single crystals","authors":"H. Shimizu, Ayako Kondo, M. Nishida, H. Takeda, T. Nishida, Tadashi Nara","doi":"10.1109/ULTSYM.2005.1603004","DOIUrl":"https://doi.org/10.1109/ULTSYM.2005.1603004","url":null,"abstract":"Electro-acoustical constants (eij T , sij E , dij) of the rare- earth calcium oxoborate RCa4O(BO3)3 (R = La, Gd, Y; RCOB) piezoelectric single crystals, which belong to the monoclinic structure with point group m, were evaluated. Their electro- acoustical constants were systematically compared to the ionic radius of the R-site ions. The piezoelectric constants d11, d12, d13, d31, d32 and d33 hardly changed with the increasing R-site ionic radius. It was confirmed that the 1/(ρ sii E ) terms, which consist of diagonal components of elastic compliances (sii E : i = 1-6) and the RCOB crystal density ρ, were closely related to the measured SAW velocities. The Rayleigh SAW velocities for the fundamental X-, Y- and Z-cuts were theoretically calculated in their crystals, which showed a good agreement with the measured values in all the fundamental cuts of their crystals. In common among their crystals, symmetrical propagation profiles were obtained on the X- and Z-cuts, on the other hand, the Y-cut did not show any symmetrical propagation ones. The Euler angles Ψ with minimum Rayleigh SAW velocities on their Y-cuts were larger than 90 o . These results in their Y-cuts were attributed to","PeriodicalId":302030,"journal":{"name":"IEEE Ultrasonics Symposium, 2005.","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132321122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Welding characteristics and temperature rises of various frequency ultrasonic plastic welding 不同频率超声波塑料焊接的焊接特性及温升

IEEE Ultrasonics Symposium, 2005. Pub Date : 2005-09-18 DOI: 10.1109/ULTSYM.2005.1602949

J. Tsujino, M. Hongoh, M. Yoshikuni, H. Miura, T. Ueoka

引用次数: 6

Fast 3D simulation of 2nd harmonic ultrasound field from arbitrary transducer geometries 从任意换能器几何形状快速三维模拟二次谐波超声场

IEEE Ultrasonics Symposium, 2005. Pub Date : 2005-09-18 DOI: 10.1109/ULTSYM.2005.1603260

Safiye Dursun, T. Varslot, T. Johansen, B. Angelsen, H. Torp

引用次数: 12

Borehole flexural waves in formations with radially varying properties 具有径向变化性质的地层中的井内弯曲波

IEEE Ultrasonics Symposium, 2005. Pub Date : 2005-09-18 DOI: 10.1109/ULTSYM.2005.1602914

B. Sinha, H. Valero, T. Ikegami, J. Pabon

{"title":"Borehole flexural waves in formations with radially varying properties","authors":"B. Sinha, H. Valero, T. Ikegami, J. Pabon","doi":"10.1109/ULTSYM.2005.1602914","DOIUrl":"https://doi.org/10.1109/ULTSYM.2005.1602914","url":null,"abstract":"Elastic wave propagation in a fluid-filled borehole is affected by near-wellbore alteration of formation properties. Near-wellbore alteration can be caused by several sources, such as overbalance drilling, borehole stress concentrations, shale swelling, near- wellbore mechanical damage and supercharging of permeable formations. Optimal completions of a well for production require both identification and estimation of the radial extent of alteration in reservoir intervals. Measured borehole flexural dispersions in the presence of radial gradients in formation properties can be inverted to estimate the radial extent of mechanical alteration. However, the presence of a tool structure that carries the acoustic transmitters and hydrophone receivers also introduces certain amount of bias on the measured borehole flexural dispersions. This paper describes the Backus-Gilbert inversion of synthetic borehole flexural data for radial variation in formation shear slowness (slowness is inverse of velocity). The inversion algorithm accounts for the tool bias on the measured data by introducing an equivalent structure of a heavy-fluid column placed concentrically with the borehole axis. This simple structure enables computation of the eigensolution for a reference homogeneous and isotropic formation that are used for calculating the data kernel in the perturbation integral equation. The solution of this integral equation yields the radial variation in the formation shear modulus in terms of fractional differences in the measured and reference dispersion at various wavenumbers. Results are presented for both radially increasing and decreasing shear slownesses away from the borehole.","PeriodicalId":302030,"journal":{"name":"IEEE Ultrasonics Symposium, 2005.","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127922632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1