G. C. Martins, P. R. Nunes, J. A. Cordioli
Federal University of Santa Catarina, Florianópolis, SC, Brazil
The use of piezoelectric materials in hearing aid loudspeakers, also called receivers, presents technical and economic advantages such as reducing the number of parts of the system and its manufacturing cost. However, the performance of such systems is still not competitive when compared to traditional electrodynamic loudspeakers. In order to achieve an appropriate performance, one option is to ...
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 ...
ÅF, Stockholm, Sweden
In this paper a pre-study on using COMSOL Multiphysics for rotordynamic analysis is presented. It is concluded that it is possible to use COMSOL Multiphysics to perform rotordynamical analysis. However, there are no standard environment for rotordynamics, hence the user has to extend the structural model with the rotordynamics effect such as gyroscopic effect and rotordynamical coefficients. By ...
J. McKenna, M. McKenna, S. Yushanov, J. Crompton, and K. Koppenhoefer
U.S. Army Engineering Research and Development Center
ACES of Columbus, LLC, Columbus, OH, USA
The propagation of shear (S) and compression (P) waves within the earth allows geologists to track seismic events and to identify subterranean structure. This work shows the strong effect of including the variation of wave speed through the top thirty meters of the earth. By including this variation in material properties, the wave arrival time and frequency content agree with experimental ...
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 ...
H. Lissek, R. Boulandet, and M. Maugard
Ecole Polytechnique Federale de Lausanne
An \"electroacoustic absorber\" is a loudspeaker, used as an absorber of sound, which acoustic impedance can be varied by electrical means. This can be achieved either by plugging passive shunt electric networks at the loudspeaker terminals (“shunt loudspeakers”) or by feeding back the loudspeaker with a voltage proportional to acoustic quantities, such as sound pressure and diaphragm normal ...
Modeling of Noise Produced by Offshore Wind Turbines with Different Foundations and Effects on the Marine Environment - new
B. Marmo , I. Roberts 
Xi Engineering Consultants, Edinburgh, Scotland, UK
Vibration produced by offshore wind turbines during their normal operation transmits through the tower into the foundation where it interacts with the surrounding water and is released as noise. The noise produced by offshore wind turbines can be detected by fish and marine mammals and may lead to alteration of their behavior. Given that noise is emitted at the interface between the foundation ...
A. Daneryd, D. Ericsson
ABB Corporate Research, Västerås, Sweden
COMSOL AB, Stockholm, Sweden
For certain classes of scientific and technical computations the cloud may offer easily accessible, scalable, and affordable gigantic computing power. A power that for these classes may lead to a step change in model and analysis complexity compared to what is feasible with dedicated clusters and similar networked solutions. Acoustics with or without interaction with coupled physics fields ...
T. Kaufmann, F. Kassubek, D. Pape , M. Lenner
ABB Corporate Research, Baden-Dättwil, Switzerland
Lamb waves are elastic waves propagating in free solid plates. In the case of plates loaded with a fluid, the equations describing these waves have to be modified to include the effects of the fluid. In our work we have tackled this problem using COMSOL Multiphysics®. We have used the two-dimensional plane strain model of the solid mechanics interface to calculate the eigenmodes of the coupled ...
Utilization of COMSOL Multiphysics® Java API for the Integration of Composite Material Properties Through a Customized User Interface - new
Indian Institute of Technology Madras, Chennai, Tamil Nadu, India
Introduction: Usage of Composite Materials properties is rapidly gaining acceptance in various industries such as aircraft manufacturing, automotive, healthcare, etc. Its main strengths are light weight material, great strength and durability, strength related to weight, corrosion resistance and design flexibility. In the process of modeling and simulation, many a time a user wants to use ...