V. Raman , A. Abbas, and S.C. Joshi
 Indian Institute of Technology, Madras
 Nanyang Technological University, Singapore
The linear acoustic pressure field is obtained by solving the homogenous Helmholtz equation using COMSOL Multiphysics. The pressure field is used to calculate the collapse pressure of the transient cavitation bubbles by using the cavity cluster approach. The regions where the local pressure exceeds the Blake threshold are potential regions of transient cavitation events. The ultrasound ...
Y.L. Rao, and G. Zhang[1-3]
 Micro/Nano Bioengineering Laboratory, Department of Biological and Agricultural Engineering, The University of Georgia
 Nanoscale Science and Engineering Center, The University of Georgia
 Faculty of Engineering, The University of Georgia
Integration of surface acoustic wave (SAW) devices with nanostructures has gained interest in the development of sensors with high sensitivity. To better design nanostructure integrated SAW devices, it is essential to model three dimensional (3-D) SAW devices and analyze the wave propagation characteristics in nanostructure-enhanced SAW devices. In this work, a 3-D finite element model of ...
P. S. K. Mylavarapu, and S. Boddapati
Defence Metallurgical Research Laboratory
Syntactic foams are hollow particle filled composites that have recently emerged as attractive materials for use in advanced structural applications in aerospace and defence industry. Ultrasonic characterization of these foams is performed extensively in order to understand the effect of porosity and particle size on the ultrasonic properties such as longitudinal velocity and attenuation. ...
C. Thiagarajan, G. Shenoy, B. S. Shenoy
ATOA Scientific Technologies Pvt Ltd, Whitefield, Bangalore, India.
Department of Mechanical & Manufacturing Engineering, Manipal Institute of technology, Manipal, India
Department of Aeronautical & Automobile Engineering, Manipal Institute of Technology, Manipal, India
Vibration and Dynamic performances of the rotating machinery are conventionally evaluated based on the dominant structural forces such as the centrifugal forces. The increase in rotational speed, miniaturization and performance, demands for improved and accurate evaluation of the vibration performance. The inclusion of coupled effects of fluid and centrifugal forces can contribute significantly ...
A. Ravi, R. Krishna, J. Christen
Arizona State University, Tempe, AZ, USA
Capacitive MEMS sensors offer high spatial resolution, sensitivity and good frequency response. In this paper, we present a circular membrane capacitive MEMS device that finds use both as capacitive micromachined ultrasonic transducer (CMUT) and pressure sensor. The MEMS device is first designed and simulated to work as a CMUT operating at about 5 MHz frequency. The device can also function as a ...
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 ...
Zhejiang Electro-Acoustic R&D Center, CAS, Zhejiang, China
扬声器的失真问题一直受电声业界的关注，尤其是谐波失真，它是影响扬声器重放声音音质的主要因素之一。 本文提出了一种基于 COMSOL Multiphysics® ...
A. Bonomo, M. Isakson
Applied Research Laboratories, The University of Texas at Austin, Austin, TX, USA
COMSOL Multiphysics® is used to address the problem of acoustic scattering from one-dimensional rough poroelastic surfaces. The poroelastic sediment is modeled following the Biot-Stoll formulation. The rough surfaces are generated using a modified power law spectrum. Both monostatic and bistatic scattering strengths are calculated. These results are compared with more conventional scattering ...
Dynamic Characterization and Mechanical Simulation of Cantilevers for Electromechanical Vibration Energy Harvesting
N. Alcheick, H. Nesser, H. Debeda, C. Ayela, I. Dufour 
Univ. Bordeaux, IMS Lab, Pessac, France
Energy harvesting from ambient vibrations has become an interesting topic for powering wireless sensor networks. Resonant microdevices based on MEMS have become of central importance at low frequency. The power produced at resonance is at least one order of magnitude larger than off frequency power since the largest strain is obtained at resonance. In order to obtain large strain for efficient ...
B. Marmo, and B. Carruthers
Reactec Ltd., Edinburgh, United Kingdom
The onshore wind turbine industry must overcome many technical, commercial, and environmental difficulties. A significant element for planning consent is operational noise. Acoustic limits are strictly enforced and can lead to near-neighbour complaints as well as contractual disputes. Reactec have diagnosed, analysed and solved a problematic tonal resonance for a major wind turbine generator ...