Acoustic Field Comparison of High Intensity Focused Ultrasound Using Experimental Characterization and Finite Element Simulation
J. L. Teja, A. Vera, L. Leija
Department of Electrical Engineering, Cinvestav-IPN, Mexico D.F., Mexico
High Intensity Focused Ultrasound (HIFU) is used as a noninvasive technique of tissue heating and ablation for different medical treatments. This paper presents a quantitative comparison of HIFU acoustic fields experimentally obtained versus simulated acoustic fields. Acoustic field characterization was realized in two HIFU transducers using water as a propagation medium. Also, simulations were ...
R. Xu , M. Guizzetti , K. Astafiev , E. Ringgaard , T. Zawada ,
 Meggitt A/S, Kvistgaard, Denmark
FEM (Finite Element Method) modelling software such as COMSOL Multiphysics® can be a powerful tool for modelling the behavior and response of piezoelectric materials and devices . Devices based on piezoelectric crystals are particularly well suited, because the polarization magnitude in crystals is predetermined and its orientation is defined by how it was cut with respect to the lattice ...
A. Arevalo , D. Castro , D. Conchouso , I. G. Foulds 
 Computer, Electrical and Mathematical Sciences and Engineering (CEMSE), King Abdullah University of Science and Technology (KAUST), Saudi Arabia
 The University of British Columbia, School of Engineering, Okanagan Campus, Saudi Arabia
For our simulation we used the Piezoelectric Devices interface. The structure was set with (clamped) fix constraint boundaries to both ends. The bottom electrode was set to be the ground for the electrostatic physics and the top electrode was set to be a Terminal with potential of 10V. A parametric sweep study was set to change the geometry, the parameters to change was the hole diameter (Holed) ...
Rakesh Kumar Pati , SK Mohammed ali, Sakuntala Mahapatra, Millee Panigrahi
MEMS Design Centre, Dept. of ETC, Trident Academy of Technology, Bhubaneswar, Odisha, India
Despite of the existing successful clinical applications, however, the interaction, i.e. artificial sensing, between the robot and the patient is still very limited. With the help of various cameras, vision is almost the only feeling that a robot can have. In order to imitate the human skin, various signals e.g., the strength of pressure, change of strength, speed and acceleration should be ...
D. Cinanni ,
 Ciare S.r.l., Italy
Today a horn driver developing is still time and cost consuming. In addition compression driver behavior depends by the horn profile. In this study is proposed a new technique to model a combination of an existing compression driver and a virtual horn, in order to predict the horn driver acoustic behavior. This procedure comprises compression driver measurement on a Plane Wave Tube and horn ...
Simulation of a New PZT Energy Harvester with a Lower Resonance Frequency Using COMSOL Multiphysics® - new
H. Elbahr, T. Ali[1,2], A. Badawi, S. Sedky
Zewail City of Science and Technology - Cairo, Cairo, Egypt
Cairo University, Cairo, Egypt
Energy harvesting from environmental vibration nowadays is feasible because of natural oscillations like that caused by air or liquid flow and by exhalation or the heartbeat of a human body. This vibration frequency is typically low (in order of less than 1 kHz). Accordingly, low-frequency vibration based energy harvesting systems are an important research topic; these systems can be used for ...
M. Cobianchi, M. Rousseau
 B&W Group Ltd, Steyning, UK
While musical instruments often rely on a body which resonates on purposefully to amplify the vibration produced by a string or a membrane, such as in a violin or a guitar, loudspeaker cabinets should not contribute at all to the total sound radiation, but aim instead to be a perfectly rigid box which encloses the drive units in charge to transform the electrical signal at their terminal into ...
T. Graf, T. Gisler, P. Sollberger, O. Schaelli
School of Engineering and Architecture, Lucerne University, Horw, Switzerland
Axisymmetric acoustic waves propagating along buried water pipes have been investigated by FEM and experimentally. Universal dispersion relations of the fundamental mode were obtained as a function of the standard dimension ratio SDR and of the material surrounding the pipe (soil, air). At low frequency there exists little dispersion and the “dc” phase velocity of the leak noise is independent ...
A. Cavuto, G.M. Revel , M. Martarelli , F. Sopranzetti 
Università Politecnica delle Marche, Ancona, Italy
Università e-Campus, Novedrate (CO), Italy
A 2D axisymmetric model was considered in order to evaluate the propagation paths of the ultrasonic waves generated inside an aluminum plate sample due to a rapid thermal expansion produced by laser pulse. Laser Doppler Vibrometer is used to experimentally validate the numerical results of the wave propagation in the material. The presented numerical model is able to identify directivity ...
J. H. Lee , S. M. Al-Said ,
 American University of Sharjah, Sharjah, United Arab Emirates
 Jordan University of Science and Technology, Irbid, Jordan
In this paper, the effect of a crack to the flow-induced vibration characteristics of supported pipes is investigated based on vibration method. In order to estimate the crack location and depth in the pipe, we need to utilize the variation of the difference between the natural frequencies of the pipe conveying fluid with and without crack. The pipe is fluid loaded via interaction with the ...