Influence of Thermal Conductivity and Plasma Pressure on Temperature Distribution and Acoustical Eigenfrequencies of High-Intensity Discharge Lamps
J. Schwieger, B. Baumann, M. Wolff, F. Manders, J. Suijker
Heinrich-Blasius-Institute of Physical Technologies, Hamburg University of Applied Sciences, Hamburg, Germany
Philips Lighting, Turnhout, Belgium
High-intensity discharge (HID) lamps are energy-efficient light sources with excellent color qualities. A three-dimensional model of a low-wattage lamp, which includes plasma, electrodes, and burner walls, was developed in COMSOL Multiphysics®. Most parameters appearing in the coupled differential equations of the model, such as viscosity, thermal and electrical conductivity are temperature ...
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 ...
N. Nama , R. Barnkob , C. J. Kähler , T. J. Huang , F. Costanzo 
 Department of Engineering Science and Mechanics, Pennsylvania State University, PA, USA
 Institute of Fluid Mechanics and Aerodynamics, Bundeswehr University Munich, Neubiberg, Germany
Introduction - The ability to precisely manipulate fluid and particles at microscales is one of the essential requirements for various lab-on-a-chip applications such as drug diagnostics, chemical synthesis etc. Recently, the nonlinear interaction of surface acoustic waves (SAW) with fluid at microscales has been utilized to achieve this aim. When surface acoustic waves interact with fluid ...
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 ...
M. Mattingly, K. McIlhany, and R. Malek-Madani
Applied Research Laboratory, The Pennsylvania State University, University Park, PA, USA
Physics Department, United States Naval Academy, Annapolis, MD, USA
Mathematics Department, United States Naval Academy, Annapolis, MD, USA
Acoustic landmine detection is accomplished using a loud speaker as an airborne source to generate low-frequency waves that enter the soil at a certain incident angle. At a specific frequency, the landmine will "vibrate" at resonance, imparting a certain velocity on the soil particles above it that is detected by a scanning Laser Doppler Vibrometer system. The ability to mathematically predict ...
W. R. Kampinga, and Y. H. Wijnant
Reden, Hengelo, Netherlands
University of Twente, Enschede, Netherlands
Three efficient alternatives to the model in COMSOL’s thermoacoustics interface are presented. The higher efficiency of these models are explained from theory and are demonstrated by means of two examples.
J. Soons[1,2], C. Steele, S. Puria
Lab of Biomedical physics, University of Antwerp, Antwerp, Belgium
Department of Mechanical Engineering, Stanford University, Stanford, USA
Sound vibrations are collected from the external environment by the eardrum and are guided to the basilar membrane in the cochlea. Pressure differences in the two scalae of the cochlea result in a traveling wave on the basilar membrane. The tiny displacements are detected by the deflection of thousands of hair cells, situated along this membrane. It is hypothesized that some 3/4 of these hair ...
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. ...
A. Arevalo , D. Castro , D. Conchouso , I. G. Foulds 
 Computer, Electrical and Mathematical Sciences and Engineering (CEMSE), King Abdullah University of Science and Technology (KAUST), Saudi Arabia
 The University of British Columbia, School of Engineering, Okanagan Campus, Saudi Arabia
For our simulation we used the Piezoelectric Devices interface. The structure was set with (clamped) fix constraint boundaries to both ends. The bottom electrode was set to be the ground for the electrostatic physics and the top electrode was set to be a Terminal with potential of 10V. A parametric sweep study was set to change the geometry, the parameters to change was the hole diameter (Holed) ...
C. Thiagarajan, Gururajan R., A. H. Baig, Prema S.
ATOA Scientific Technologies Pvt Ltd, Whitefield, Bangalore, Karnataka India
University of Southern Queensland, Toowoomba Qld 4350, Australia.
RMK Engineering College, Chennai, Tamil Nadu, India
Stethoscope is in use for more than 200 years for medical diagnostics, especially for auscultation. Recently, the unprecedented growth in mobile technology revived the use of stethoscope for Telehealthcare. Digital or electronic stethoscopes are increasingly researched for use in Telehealthcare. This paper mainly focuses on the acoustical and multiphysics design aspects of the stethoscope for ...