M. Zampolli, N. Malm, and A. Tesei
NURC NATO Research Centre, La Spezia, Italy
COMSOL AB, Stockholm, Sweden
Perfectly matched layers (PML) are an efficient alternative for emulating the Sommerfeld radiation condition in the numerical solution of wave radiation and scattering problems. The key ingredient of the PML formulation is the complex scaling function, which controls the anisotropic damping of the PML. The objective of this study is to propose a modified complex scaling function capable of ...
P.R. Basha, B. Mishra, and A. Zachariah
School of Electronics Engineering, VIT University, Vellore, Tamil Nadu, India
The realization of miniature SAW device is compatible on CMOS device for mobile and wireless communication system has become very important in recent years. Acoustic wave propagation along the surface of a piezoelectric material provides a means of implementing a variety of signal processing devices at frequency ranging from several MHz to a few GHz. In this work, a Miniature SAW device is ...
S.L. Firebaugh, E.A. Leckie, J.A. Piepmeier, and J.A. Burkhardt
United States Naval Academy, Annapolis, Maryland, USA
Microrobotics has promising applications in microsurgery and microassembly. A challenge in these systems is interfacing with the robot. This project explores crawling robots that are powered and controlled through a global mechanical vibration field. By controlling the frequencies present in the vibration field, the user can then steer the robot. The “robot” has a rectangular body with ...
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 ...
Beam Structure As an Acoustic Wave Sensor: A Study of the Effect of Sensor Design on Its Sensitivity to Noise
F. Akasheh, A. Biddle, W.S. Shepard Jr., and B.B.B. Zhang
Tuskegee University, Tuskegee, AL, USA
University of Alabama, Tuscaloosa, AL, USA
The detection and identification of the location of a sound source is commonly done using arrays of microphones. A recent new alternative approach has been proposed which involves the use of continuous structures, such as beams or plates, as acoustic wave sensors. The sound wave impinging on the surface of the structure causes it to vibrate and the measured surface displacements can then be used ...
JBL Professional, Northridge, CA, USA
The author presents an overview of methods to build virtual prototypes of both horns and loudspeaker drivers which allows a significant reduction in the number of physical prototypes, as well as reduced development time. This paper will present some of the practical results from work the author has performed in the course of designing both transducers and horns using COMSOL Evolution of the ...
A-S.Moreau, H.Lissek, and F. Bongard
Ecole Polytechnique Fédérale de Lausanne, Switzerland
JAST SA, Antenna Systems, Lausanne, Switzerland
In this context, a one-dimensional acoustic transmission line, exhibiting metamaterial properties, is presented. It is composed of an acoustic waveguide, periodically loaded with membranes having the function of series capacitances, as well as transversally connected open channels (denoted stubs) having the function of shunt inductances. A validation of the transmission line design is made with ...
Two-Dimensional FEM Analysis Of Brillouin Gain Spectra In Acoustic Guiding And Acoustic Antiguiding Single Mode Optical Fibers
Y.S. Mamdem, X. Pheron, F.Taillade, Y. Jaouën, R. Gabet, V. Lanticq[1,3], G. Moreau, A. Boukenter, Y. Ouerdane, S. Lesoille, and J. Bertrand
EDF R&D, Chatou, France
ANDRA, Chatenay-Malabry, France
LCPC, Paris, France
Telecom ParisTech, Paris, France
Laboratoire Hubert Curien, Saint-Etienne, France
We present a full modal -analysis of optical and acoustic properties based on two-dimensional finite-element method (2D-FEM) for Brillouin Gain spectrum (BGS) determination in optical fibers with COMSOL. This model enables us to predict precisely the BGS of any kind of silica fiber knowing well the geometry of doping composition. The results of numerical modeling have shown good agreement in ...
R. Venegas, and O. Umnova
Acoustics Research Centre, University of Salford, Salford, United Kingdom
Granular materials have been conventionally used for acoustic treatment due to their sound absorptive and sound insulating characteristics. An emerging field is the study of acoustical properties of multi-scale porous materials. An example of these is a double-porosity granular material in which the grains are porous themselves. In this work, a computational methodology for modelling this type ...
C. Peyrega, and D. Jeulin
Center of Mathematical Morphology, Mines ParisTech, Fontainebleau, France
This study is a part of the Silent Wall ANR project, to which the Center of Mathematical Morphology is associated. Its main objective is to build an acoustical and thermal insulating system for buildings, composed of fibrous materials. The material is composed of two phases: the fibrous network and the air surrounding it. At the microscopic scale the absorption of the acoustic wave is mainly due ...