E. Gutierrez-Miravete, W. L. Saunders II, K. Pendley
Rensselaer at Hartford, Hartford, CT, USA
General Dynamics Electric Boat, Groton, CT, USA
United Technologies - Pratt & Whitney, East Hartford, CT, USA
The determination of the modes of vibration of Functionally Graded-Metal-Ceramic Composite plates is important in practice in order to prevent undesired resonances in structural components. This paper describes the application of COMSOL Multiphysics® software for the determination of the modes of vibration of Aluminum A356-T6Alloy-ZrO2 FG-MCC square plates.
Design and Simulation of an Orbiting Piezoelectric MEMS Gyroscope Based on Detection of Phase-Shift Signals - new
S. Gorelick, J. R. Dekker, B. Guo, H. Rimminen
 VTT Technical Research Centre of Finland, Espoo, Finland
The feasibility of phase-sensitive detection of angular-rates using bi-directional orbiting piezoresonators suspended by thick annular springs with thin-film aluminium nitride piezoactuators on top of them was investigated. The ring-shaped flexures are more suitable for supporting the orbiting motion due to their angle-dependent spring constant. The response of the orbiting resonators to angular ...
B. Goldsberry, M. Isakson
Applied Research Laboratories, The University of Texas at Austin, Austin, TX, USA
Measuring geoacoustic parameters of underwater sediments is important for accurate modeling of underwater acoustic propagation. While the density and compressional wave speeds can be directly measured in sediments, shear wave speeds are difficult to measure because they are highly attenuated. However, shear wave speeds can be indirectly determined through measurement of Scholte interface wave ...
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 ...
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 ...
Modeling of Ultrasonic Transducers and Ultrasonic Wave Propagation for Commercial Applications Using Finite Elements with Experimental Visualization of Waves for Validation - new
D. R. Andrews
Cambridge Ultrasonics, Over, UK
Finite element (FE) modelling of ultrasonic propagation using COMSOL Multiphysics® simulations can be used to create images of waves. Unfortunately, in time-stepping solutions, it is possible for numerical instabilities to grow large and dominate the solution adversely. Any design of transducer that is based upon poorly-configured FE models is unlikely to perform as expected and will almost ...
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 ...
D. Groulx, A. Bharath, S. Campbell
Department of Mechanical Engineering, Dalhousie University, Halifax, NS, Canada
The field of underwater acoustics research is constantly growing with the ongoing improvement of acoustic measuring techniques. An acoustic hydrophone receiver is a passive listening device which is widely used in biological research and sonar technology. The hydrophone however suffers from turbulence generated noise created by its presence in ever faster flow. This work aims to analyze the ...
NATO Undersea Research Centre, La spezia
In water we can’t see far, because light and electromagnetic waves are absorbed over relatively short distances. In contrast, sound travels very well in water In fact it is well known that marine mammals rely on sound for communication over large distances, and some of them even use sound to locate their target while hunting. In this presentation we provide an overview of the principles of ...
P. S. K. Mylavarapu, and S. Boddapati
Defence Metallurgical Research Laboratory
Syntactic foams are hollow particle filled composites that have recently emerged as attractive materials for use in advanced structural applications in aerospace and defence industry. Ultrasonic characterization of these foams is performed extensively in order to understand the effect of porosity and particle size on the ultrasonic properties such as longitudinal velocity and attenuation. ...