P. Olsson, F. Larsson, A. Khlopotin, S. Razanica
Chalmers University of Technology, Gothenburg, Sweden
In solid mechanics, there is considerable interest in achieving “invisibility”. The applications in mechanics include protection of structures and parts of structures from potentially harmful transient waves and steady state vibrations. A suggested large scale application is that protection against seismic waves from earthquakes could be achieved by using cloaking to re-route the waves around ...
L. Spicci, M. Cati
Esaote, Firenze, Italy
Ultrasound imaging probes are widely used for several types of diagnosis applications. In the present work we focus our attention on a disk-type probe, which is widely used in CW and PW operating conditions. In particular we present a 2D-axial symmetry FEM for the probe, capable to predict both the operative temperature values at different driving signal frequencies, both the heating dynamics. ...
ACOUSTICS@MBD CONSULTANTS, LLC, Westborough, MA, USA
There is a practical interest among composite materials manufacturers to high-speed accurate non-destructive evaluation (NDE) technology for voids inspection when these voids are natural components of such complex structures like resin insulated layer of double-sided copper-clad laminates. Model based design (MBD) of NDE system is one of principal solutions for voids inspection in such ...
N. Alcheikh, C. Ayela, I. Dufour
Univ. Bordeaux, IMS Lab, Pessac, France.
Electrostrictive polymers have been of significant interest over the last years for energy harvesting. Principle is based on the conversion of a mechanical deformation into electricity. The stored energy basically depends on the mechanical strain induced into an electrostrictive polymer by the mechanical resonant vibration of a microcantilever supporting the electrostrictive layer. In this work, ...
L. Martinelli, and A. Lamberti
Universita di Bologna, Italy
Objective of this contribution is to show how to implement the Mild Slope Equations with COMSOL Multiphysics. These equations are commonly used to study the propagation of waves in harbors. Some interesting features are presented, namely the use of weak terms (used for the modelling of the source term); the evaluation of a smooth phase gradient from the complex dependent variable; a robust ...
R. Sisto, L. Cerini, D. Mambro, A. Moleti, F. Sanjust
INAIL Research, Monteporzio Catone, Italy
Università di Roma, Tor Vergata, Italy
The otoacoustic emissions (OAEs) are acoustic signals emitted by the inner ear as a consequence of the activity of a nonlinear feedback mechanism capable of amplifying the signal near to the hearing threshold level. The otoacoustic emissions can be used as an acoustic imaging of the cochlear functionality. They are used in clinics for screening purposes but due to the extreme variability ...
M. Mattingly, K. McIlhany, and R. Malek-Madani
Applied Research Laboratory, The Pennsylvania State University, University Park, PA, USA
Physics Department, United States Naval Academy, Annapolis, MD, USA
Mathematics Department, United States Naval Academy, Annapolis, MD, USA
Acoustic landmine detection is accomplished using a loud speaker as an airborne source to generate low-frequency waves that enter the soil at a certain incident angle. At a specific frequency, the landmine will "vibrate" at resonance, imparting a certain velocity on the soil particles above it that is detected by a scanning Laser Doppler Vibrometer system. The ability to mathematically predict ...
R. C. Thiagarajan
ATOA Scientific Technologies Private Limited
Ultrasonic acoustic waves usually encounter interfaces with significant impedance mismatch in practical medical or industrial imaging applications. A transparent interface can help to improve the performance of medical and industrial imaging and overall innovative applications. Similarly, a broadband total reflection interface can help to improve the architectural or transportation barrier ...
V.M. Acosta, E. Riera, G. Rodriguez, A. Pinto, A. Cardoni, J.A. Gallego-Juárez
Power Ultrasonics Group, CSIC, Serrano, Madrid, Spain
Pusonics, Arganda del Rey, Madrid, Spain
This work describes the design methodology and development of piezoelectric transducers for applications in fluids with COMSOL_Multiphysics. In these linear models for the acoustic-structure interaction approximate numerical solutions have been obtained. In order to perform the calculations, simplifications are only valid for low-power sound waves. Numerical modeling of piezoelectric transducers ...
K. Mcilhany, and J.C Hernandez
U.S. Naval Academy, Annapolis, MD, USA
Acoustic Imaging of hand movement is being studied with COMSOL and Matlab. A hardware implementation is being pursued that will be an array of 16x16 ultra-sonic speakers placed in a grid facing a similar grid of 16x16 microphones, operating at 40kHz. COMSOL is used to repeatedly calculate the diffraction pattern from a small scattering center, approximately 1.0cm in diameter. In conjunction ...