Analysis of a Plasma-Mediated Photoacoustic Response From Plasmonic Nanoparticles in Ultrashort Regime
A. Hatef , B. Darvish , A. Dagallier , C. Boutopoulos , M. Meunier ,
 Nipissing University, North Bay, ON, Canada
 École Polytechnique de Montréal, Montréal, QC, Canada
Over the last decade, plasmonic nanoparticles (PNPs) have received growing interest as exogenous contrast agents in the thermal expansion based photoacoustic (PA) imaging technique in biomedical applications . Such functionality is due to the localized surface plasmon resonance (LSPR) created by the light-induced coherent oscillation of the conduction electrons in the PNPs. In the near-field ...
C. J. Morgan , S. R. Fischbach ,
 Jacobs ESSSA Group, NASA Marshall Space Flight Center, Huntsville, AL, USA
This study evaluates the effect of injector resistance on the mode shapes and complex eigenfrequencies of an injector/combustion chamber system by defining a high Mach-flow, potential flow form of the convective wave equation in the Coefficient Form PDE Mathematics interface. Background steady-state flow conditions are determined through a NASA Marshall Space Flight Center in-house fluid ...
D. Neihguk , M. L. Munjal , A. Prasad ,
 Mahindra & Mahindra Ltd, Chennai, India
 Indian Institute of Science, Bangalore, India
Perforated pipes are extensively used to control exhaust noise in automobiles [1-4]. The energy loss associated with the perforations leads to back pressure which needs to be quantified and minimized . An objective approach presented in  is the introduction of friction factor for perforated ducts as a function of the porosity. In this article, the utilization of the CFD Module of COMSOL ...
Mads Jakob Herring Jensen
Dr., Widex A/S, Denmark
In modern hearing aids, the performance of directional microphone systems is dependent on both the acoustics around thehearing aid and on the specific signal processing algorithms. The sound pressure at the microphone inlets depends on microphone location in the hearing-aid shell, the inlet shape, and on the placement of the hearing aid on the head of the user. In the present work, the ...
S. De Paolis, F. Lionetto, and A. Maffezzoli
Department of Innovation Engineering, University of Salento, Lecce, Italy
Finite element analysis has been used to model the ultrasonic wave propagation both in a custom made transducer and in the tested polymer sample. The model consists of acoustic (passive elements) and electroacoustic (active elements) transmission lines. The simulation of the acoustic propagation accounts for the interaction between the transducer and the materials in the buffer rods, and the ...
A-S. Moreau, H. Lissek, and R. Boulandet
EPFL-STI-IEL-LEMA, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
In this paper, the underlying concept of electroacoustic absorbers is studied with the help of Comsol Multiphysics® Acoustics Module. Among the different ways to obtain variable acoustic properties on an electroacoustic transducer's voicing face, there is the shunting of the transducer's electrical input. With such shunt devices, the acoustic impedance that the transducer's membrane presents ...
Guided Wave in Engineering Structures Using Non-Contact Electromagnetic Acoustic Transducers: A Numerical Approach for the Technique Optimisation
S. Soua, A. Raude, and T-H. Gan
NDT Technology Group, TWI Ltd, Cambridge, United Kingdom
There are over 10 million kilometers of pipes and pipelines around the world that carry hazardous fluids and gases. Fluids include oil, oil products, chemicals such as solvents, caustics, acids, corrosives and combustibles often at high pressure and temperature. These pipes are susceptible to corrosion if they are not protected properly by the environment or the contents. Inspection of pipes is ...
S.L. Firebaugh, F. Roignant, and E.A. Terray
United States Naval Academy, Annapolis, Maryland, USA
Polytechnique Nantes, Nantes, France
Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, USA
A fast, high-sensitivity detector is required for studies of environmentally relevant gases. Photoacoustic spectroscopy (PAS), an absorption spectroscopy technique in which absorption is detected as sound, is explored as a possible solution. A tuning-fork based PAS sensor is modeled using COMSOL. The model combines the acoustic and piezoelectric modules and also includes viscous damping. The ...
A.K. Namdeo, N. Ramakrishnan, and H.B. Nemade
Department of Electronics and Communication Engineering, Indian Institute of Technology Guwahati, Guwahati, India
Centre for Nanotechnology, Indian Institute of Technology Guwahati, Guwahati, India
This paper presents finite element method (FEM) simulation study of the generation of bulk acoustic waves (BAWs) and their effect on the performance of surface acoustic wave (SAW) devices, using COMSOL Multiphysics. A SAW delay line structure using YZ-cut lithium niobate substrate is simulated. The radiation of the bulk waves in all angles into the interior of the substrate is analyzed. The bulk ...
C. Peyrega, and D. Jeulin
Center of Mathematical Morphology, Mines ParisTech, Fontainebleau, France
This study is a part of the Silent Wall ANR project, to which the Center of Mathematical Morphology is associated. Its main objective is to build an acoustical and thermal insulating system for buildings, composed of fibrous materials. The material is composed of two phases: the fibrous network and the air surrounding it. At the microscopic scale the absorption of the acoustic wave is mainly ...