Poznan University of Technology, Poland
This paper examines a sound propagation without airflow through circular ducts with spiral element inside. Models are numerically computed in three-dimensions. The spiral element in the duct is a newly analyzed acoustical element, geometrically similar to the well-known Archimedes screw. It can be applied significantly in ducted systems, such as ventilation, air-conditioning and heat ...
M. Herring Jensen
Widex A/S, Vaerloese, Denmark
In this study we model the sound attenuation properties of a hearing aid earmold tube. The model includes thermoviscous acoustic effects and it couples structural vibrations to the external acoustic field. Moreover, the finite element domain is coupled at two boundaries with an electroacoustic model of a hearing aid and an acoustic 2-cc coupler.
J.S. Crompton, L.T. Gritter, S. Yushanov, K.C. Koppenhoefer, and D. Magyari
AltaSim Technologies, LLC, Columbus, OH, USA
Golden Acoustics, Detroit, MI, USA
The preferred acoustic response of recording studios, auditoriums and conference halls is to have an even energy response over the entire room and throughout full audio spectrum. This can be accomplished by using acoustic panels with complex surface structures that scatter acoustic waves and diffuse sound level variability over the room volume or through the use of sound absorbing materials to ...
M. Hedges and Y.W. Lam
Acoustics Research Centre, School of Computing, Science & Engineering, University of Salford, Salford, United Kingdom
Monitor Audio Ltd., Rayleigh, Essex, United Kingdom
Loudspeaker simulation is used to inform the designer as to the performance of a design. In recent years the Finite Element Method (FEM) has been used to model the mechanical and acoustical attributes of a loudspeaker with varying success. This paper shows how a model that incorporates the magnetic, electromagnetic, mechanical and acoustical domains performs. These domains will be coupled where ...
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 ...
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 data. ...
K. Koppenhoefer, S.Yushanov, and M.H. McKenna
AltaSim Technologies, LLC, Columbus, Ohio, USA
U.S. Army Engineering Research and Development Center
Aging infrastructure requires frequent inspections to assess their structural integrity. However, the large amount of existing infrastructure, and the distance between these structures present significant challenges to inspectors. Acoustics-based technologies represent a simple, and relatively inexpensive, technique to monitor the integrity of a structure. To develop these techniques, designers ...
On The Use of a Diffusion Equation Model for Sound Energy Flow Prediction in Acoustically Coupled Spaces
Y. Jing, and N. Xiang
Rensselaer Polytechnic Institute, Troy, NY, USA
This paper studies sound energy flows through an aperture across two coupled spaces using a diffusion equation model. The so-called double sloped sound energy decay is believed to be caused by the sound energy exchange through the aperture coupling the two rooms. The room diffusion equation is first solved by COMSOL, then the time dependent energy flow is visualized via COMSOL arrow plotting, ...
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 ...
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 ...