Zeugin Bauberatungen AG
Especially in large offices and call centers the noise pollution of Employees and mutual disturbance is an actual problem. The existing distribution of the sound pressure level in a range of frequency from 100 – 250 Hz show significant noise pollution also at remote workplaces for the current state of the examined large office. For improvements the influence of compact wideband sound ...
D. P. Elford, L. Chalmers, F. V. Kusmartsev, and G. M. Swallowe
Department of Physics
The results of numerical modelling of sonic crystals with resonant array elements are reported. The acoustic band structure and transmission characteristics of such systems have been computed with the use of finite element methods. An existence of a separate attenuation mechanism associated with the resonant elements, which increases performance in the lower frequency regime has been ...
M. Zebian[1,2], J. Hensel , and T. Fedtke
Physikalisch-Technische Bundesanstalt, Braunschweig, Germany
International Graduate School of Metrology, Braunschweig, Germany
Otoacoustic emission (OAE) tests provide an objective examination of the cochlear function. However, the validity of OAE tests is affected negatively by calibration errors. This report sheds light on the evanescent waves arising at the interface between the OAE probe and the ear canal, and analyses the impact of minor eartip modifications on the acoustic length estimation of ear canals, using ...
Acoustics@ MBD Consultants LLC.
Applied 2D scale model presents a semi-realistic design or a microphone and shows the main mechanical, magnetic coil and electrical parts. Some non-vital elements are excluded for better focusing on acoustic properties of the microphone. The models are tested for frequency response, acoustic power loss, directivity patterns as well design and materials optimization. Based on 2D model analysis ...
S. L. Pinjare, V. S. Nagaraj, S. N. Savitha, S. Kesari, M. S. Sagar, and K. R. Roshan
Nitte Meenakshi Institute of Technology
The MEMS microphone is also called microphone chip or silicon microphone. The pressure sensitive diaphragm is etched directly into a silicon chip by MEMS techniques and is usually accompanied with integrated preamplifier. Most MEMS microphones are variants of the condenser microphone design. The MEMS microphone has been successfully fabricated and tested in an anechoic chamber. The microphone ...
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 ...
Tohoku Institute of Technology
This paper is in Japanese.
J. Muraoka, and T. Suzuki
Yamagata Research Institute of Technology
The traveling wave ultrasonic vibration disks for dispersion of particles were designed by using of FEM analysis. The vibration disks are required specific vibration pattern, which contains three nodal lines. The vibration disk thickness was calculated to be matched the resonance frequency of bolted langevin type transducer and the specific vibration pattern. The alignment of the transducer was ...
Simulation Analysis of Acoustic Radiation Force under Ultrasound Exposure and Effect to Microbubbles in Flow
Tokyo University of Agriculture & Technology
This paper is in Japanese.
H. Bruus, P.B. Muller, R. Barnkob, M.J.H. Jensen
Technical University of Denmark, Kongens Lyngby, Denmark
COMSOL, Kongens Lyngby, Denmark
We have simulated the ultrasound-induced acoustophoretic motion of microparticles suspended in an aqueous solution. The full first-order thermoviscous acoustics equations have been implented on a rectangular microfluidic 2D domain excited with an ultrasound field tuned to resonance near 2 MHz. The micrometer-thin but crucial viscous boundary layers at the rigid walls have been fully resolved. The ...