Ici vous trouverez les présentations issues des Conférences COMSOL à travers le monde. Réalisées par des utilisateurs de COMSOL Multiphysics, ces présentations explorent tous les domaines actuels d'innovation. Les applications couvrent pratiquement tous les secteurs industriels et impliquent des phénomènes électriques, mécaniques, fluidiques et chimiques. Utilisez la recherche rapide pour trouver les présentations les plus intéressantes dans votre domaine d'intérêt.

Heat Drain Device on Ultrasound Imaging Probe - new

G. Vigna[1], L. Spicci[1]
[1]Esaote SPA, Florence, Italy

Self-heating is a problem to consider for Ultrasound Imaging probes. Since the probe is in contact with the skin, it’s necessary to find a solution to lower the front face temperature in order to avoid patient discomfort, even at the most demanding operating condition. One solution consists in the design of a device that drains the heat from the front to the rear of the transducer, where a ...

Simulation of Acoustical Transfer Paths for Active Noise Control

L. Fromme [1], J. Waßmuth [1], D. Wehmeier [1],
[1] Bielefeld University of Applied Sciences, Bielefeld, Germany

The knowledge of the acoustical transfer paths in active noise control systems is very important for the performance of the system. Unfortunately, simulation is challenging since even simple configurations require comprehensive experience in physics and modeling. Two test setups were chosen for basic investigations on modeling, simulation and validation. The first results presented here are ...

Lamb Waves in Fluid-Loaded Plates

T. Kaufmann[1], F. Kassubek[1], D. Pape [1], M. Lenner[1]
[1]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 ...

Support-Q Optimisation of a Trapped Mode Beam Resonator - new

T. H. Hanley[1], H. T. D. Grigg[1], B. J. Gallacher[1]
[1]Newcastle University, Newcastle-Upon-Tyne, UK

Introducing a disorder into a finite periodic oscillatory system induces the presence of a 'trapped mode': a mode in which the displacement field is localised to the region of the disorder. A main inhibitor to MEMS resonators achieving a high quality (Q) factor is energy radiation through the support to the substrate. The trapped modes present a way to tune this to a minimal value. An initial ...

Experimental and Theoretical Investigation of Acoustic Metamaterial with Negative Bulk-Modulus

N. R. Mahesh, and P. Nair
SSN College of Engineering
Chennai
Tamil Nadu, India

Acoustic metamaterials are structured materials of negative mass density or negative bulk-modulus or both of them. Materials are tailored in sub-wavelength dimensions so as to get these negative properties. This paper compares the result of an experimental investigation of acoustic metamaterial with negative bulk-modulus to its COMSOL modeling. The resonance characteristics of single ...

Numerical Simulation of Phonon Dispersion Relations for Phononic Crystals

G. Zhu[1], E.M. Dede[1]
[1]Toyota Research Institute of North America, Ann Arbor, MI, USA

In previous work, a two-dimensional (2D) model was carried out to simulate the phononic band structure of a phononic crystal with square lattice structure, but this model did not account for the out-of-plane phonon dispersions [1]. In fact, for 2D films used for coating materials, it is more interesting to understand their cross-plane properties. In this work, the phonon dispersion relation of ...

Design of Electroacoustic Absorbers Using PID Control

H. Lissek, R. Boulandet, and M. Maugard
Ecole Polytechnique Federale de Lausanne
Lausanne, Switzerland

An \"electroacoustic absorber\" is a loudspeaker, used as an absorber of sound, which acoustic impedance can be varied by electrical means. This can be achieved either by plugging passive shunt electric networks at the loudspeaker terminals (“shunt loudspeakers”) or by feeding back the loudspeaker with a voltage proportional to acoustic quantities, such as sound pressure and diaphragm normal ...

Surface Acoustic Wave Scattering Matrix Evaluation Using COMSOL Multiphysics®: Application to Surface Acoustic Wave Transmission Through 2D Surface Phononic Crystal

S. Yankin[1,2], A. Talbi[1], V. Preobrazhensky[1,3], P. Pernod[1], O. Bou Matar[1], A. Pavlova[1]
[1] Joint International Laboratory LICS/LEMAC, IEMN UMR CNRS 8520, EC Lille, Villeneuve d'Ascq, France
[2] Saratov State University, Saratov, Russia
[3] Wave Research Center, Russian Academy of Sciences, Moscow, Russia

This contribution is dedicated to numerical analysis of SAW propagation though 2D surface phononic crystal (PnC) and FE method is nowadays one of most common tool for such calculation. The device under investigation consists of two dispersive IDT and lattice of ferromagnetic pillars realized on 128°YX LiNbO3. In addition to dispersion curves calculations this work describes the results of ...

Simulation Studies on the Design of a Helmholtz Resonator type Underwater Acoustic Sensor

Karthi Pradeep[1], G. Suresh[2], V. Natarajan[2],
[1]National Institute of Technology, Tiruchirappalli, Kerala, India
[2]Naval Physical & Oceanographic Laboratory (NPOL), Kochi, Kerala, India

A Helmholtz resonator type acoustic sensor has been designed using analytical method and finite element modeling software, COMSOL Multiphysics®. The acoustic sensor is an aluminium double frustum, hour glass, shaped with the resonator at the bottom and an acoustic horn above to amplify the incoming acoustic signal. The horn provides a broad amplification of the incoming acoustic signal while the ...

FEM Analysis of Flamelet Wrinkling in a Diffusion Flame - new

Y. Li[1], T.C. Lieuwen[2], J. Zhou[1], H. Cao[1]
[1]Zhengzhou University, Zhengzhou City, Henan Province, China
[2]Georgia Institute of Technology, Atlanta, GA

One can hardly get the exact analytic solution of a full time-dependent convection-diffusion equation, for describing the dynamics of a non-premixed flamelet. The analytic solution of the linearized form with such a model was studied by MATLAB®. And also, a numerical computation was made with the linearization model in COMSOL Multiphysics® software, to provide a perfect accordance with the ...