S. Ni, C. Yang Koh, S. Kooi, and E. Thomas
Institute for Soldier Nanotechnologies
Dept. of Materials Science and Eng.
Recently, the concepts of fractal geometry have been introduced into electromagnetic and plasmonic metamaterials. With their self-similarity, structures based on fractal geometry should exhibit multi-band character with high Q factors due to the scaling law. However, there exist few studies of phononic metamaterials having fractal geometry. COMSOL is used to investigate vector elastic and ...
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 ...
Solving the Inverse Problem of Resonant Ultrasound Spectroscopy on Dumbbell-shaped Compression Samples Using COMSOL Multiphysics®
M. C. Golt
U.S. Army Research Laboratory*, Aberdeen Proving Ground, MD, USA
*Contracted through Dynamic Science, Inc.
The dumbbell geometry is an ideal shape for testing the compressive strength of advanced ceramic materials. This paper details the combined use of COMSOL Multiphysics® and LiveLink™ for MATLAB® for determining the elastic properties of dumbbell-shaped samples by measuring their acoustic resonance frequencies. Degenerate bending modes which are sensitive to inhomogeneities or machining defects ...
Y. Mulchand , A. Pooransingh , R. Latchman ,
 The University of the West Indies, St. Augustine, Trinidad and Tobago
The aim of this paper is to determine the location of the “sweet spot” for a selected cricket bat commonly used in the sport. Knowledge of the “sweet spot” is important in delivering a shot that utilizes the optimal zone of the bat that corresponds to the maximum power of the stroke. A model of the cricket bat was constructed in the Structural Mechanics Module of COMSOL Multiphysics® Software ...
M. Cobianchi and R. Magalotti
 B&C Speakers S.p.a., Bagno a Ripoli, FI, Italia
In modern live sound reinforcement there is a growing use of line sources, obtained through the stacking of many loudspeakers with properly controlled wavefront shape. Thus the use of waveguides is mandatory in order to modify the shape and size of the wavefront exiting from professional compression drivers. With the help of COMSOL Multiphysics®, we have designed a waveguide featuring an ...
V. Chatziioannou, and W. Kausel
Institute of Music Acoustics
University of Music and Performing Arts
The vibration of the walls of brass wind instruments has been a subject of study in the field of musical acoustics throughout the last decades. The amplitude of such vibrations, stimulated by the oscillating air pressure inside the instrument bore, is very small compared to the dimensions of the instrument. However, it has been recently shown that at the flaring regions of the bell of brass ...
G. F. Greco , I. K. S. Hermont , B. P. Murta , T. B. Romero , P. H. Mareze , A. Lenzi , J. A. Cordioli ,
 Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
 Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
This study aims to develop and validate a finite element numerical model to represent the Insertion Loss (IL) promoted by the enclosure of a sound source. For the validation, a enclosure prototype was built in wood and the IL was measured in laboratory. The idea is to develop an efficient numerical model that would be suitable for enclosure's design and optimization. The problem was modeled ...
K. Kryniski , A. Trangard ,
 ABB Corporate Research, Västerås, Sweden
In addition to using advanced functions built-into the engine of the COMSOL Multiphysics® software, we integrate dynamic properties of rotating components that are measured or pre-computed. Here, it is shown how to integrate fluid-film characteristics and take advantage of post-processing and graphics to present the results to the customers using the Cloud. COMSOL® simulations of rotor-bearing ...
G.D. Cole, M. Aspelmeyer, and I. Wilson-Rae
University of Vienna, Vienna, Austria
Technical University Munich, Munich, Germany
Micro-and nanoscale mechanical resonators have recently emerged as ubiquitous devices for use in advanced technological applications, for example in mobile communications and inertial sensors, and as novel tools for fundamental scientific endeavors. We report a significant advancement towards understanding and controlling support-induced losses through the demonstration of an efficient numerical ...
R. Langkemper , R. Külls , J. Wilde , S. Nau , S. Schopferer ,
 Fraunhofer-Institut für Kurzzeitdynamik, Ernst-Mach-Institut, EMI, Freiburg, Germany
 Albert-Ludwigs-Universität Freiburg, Institut für Mikrosystemtechnik, Freiburg, Germany
Acceleration is an important quantity to be measured in high-speed dynamics. A new piezoresistive sensor for the measurement of high-amplitude, short-duration transient accelerations of up to 100,000 g has been developed at the Fraunhofer EMI. Its figure of merit (sensitivity x resonance frequency²) is about one order of magnitude higher than that of comparable state-of-the-art sensors. ...