In questa sezione troverete i lavori presentati alle Conferenze mondiali COMSOL. Le presentazioni descrivono ricerche e prodotti innovativi progettati con COMSOL Multiphysics da colleghi di tutto il mondo. I temi delle ricerche presentate abbracciano un'ampia gamma di settori produttivi e aree applicative, in ambito elettrico, meccanico, fluidodinamico e chimico. Lo strumento di Ricerca Rapida vi permetterà di trovare le presentazioni che si riferiscono all'area di vostro interesse.

Acoustic Wave Propagation in Water Filled Buried Polyethylene Pipes - new

T. Graf[1], T. Gisler[1], P. Sollberger[1], O. Schaelli[1]
[1]School of Engineering and Architecture, Lucerne University, Horw, Switzerland

Axisymmetric acoustic waves propagating along buried water pipes have been investigated by FEM and experimentally. Universal dispersion relations of the fundamental mode were obtained as a function of the standard dimension ratio SDR and of the material surrounding the pipe (soil, air). At low frequency there exists little dispersion and the “dc” phase velocity of the leak noise is independent ...

Laser-Ultrasonics Wave Generation and Propagation FE Model in Metallic Materials

A. Cavuto[1], G.M. Revel [1], M. Martarelli [2], F. Sopranzetti [2]
[1]Università Politecnica delle Marche, Ancona, Italy
[2]Università e-Campus, Novedrate (CO), Italy

A 2D axisymmetric model was considered in order to evaluate the propagation paths of the ultrasonic waves generated inside an aluminum plate sample due to a rapid thermal expansion produced by laser pulse. Laser Doppler Vibrometer is used to experimentally validate the numerical results of the wave propagation in the material. The presented numerical model is able to identify directivity ...

COMSOL Analysis of Acoustic Streaming and Microparticle Acoustophoresis

H. Bruus[1], P.B. Muller[1], R. Barnkob[1], M.J.H. Jensen[2]
[1]Technical University of Denmark, Kongens Lyngby, Denmark
[2]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. ...

Analyzing Muffler Performance Using the Transfer Matrix Method 

K. Andersen
Dinex Emission Technology A/S, Middelfart, Denmark

Exhaust noise must meet legislation targets, customer expectations and cost reduction which call for design optimization of the exhaust systems in the design phase. One solution is to use 3 dimensional linear pressure acoustics and calculate the transfer matrix of the muffler. The transfer matrix is the basis for calculating either the insertion loss or transmission loss of a muffler. The 3D ...

Simulation of Impact Damage in a Composite Plate and Its Detection

V. Pavelko[1], I. Pavelko[1], M. Smolyaninovs[1], H. Pffeifer[2], M. Wevers[2]
[1]Riga Technical University, Riga, Latvia
[2]Catholic University Leuven, Leuven, Belgium

A problem of damage prediction in aircraft structure and its non-destructive evaluation is very important for aircraft structural health assessment. The analysis of the features of direct impact of thin-walled laminate component of aircraft was performed by COMSOL Multiphysics software. Mainly the GFRC and CFRC laminates were selected in form either thin separate plate or sandwich structure. The ...

Effect of Length and Porosity on the Acoustic Performance of Concentric Tube Resonators

D. Neihguk [1], A. Prasad [1],
[1] Mahindra & Mahindra Ltd., Chennai, India

The acoustic performance of an acoustically short Concentric Tube Resonator (CTR) is investigated to find an optimum porosity for a given length to diameter ratio. The study is motivated by the following practical difficulties encountered in automotive exhaust noise control: 1. Increasing trend of downsized engine and increase in power to weight ratio of engine for better fuel economy. 2. The ...

Simulation of Acoustic Energy Harvesting Using Piezoelectric Plates in a Quarter-Wavelength Straight-Tube Resonator

B. Li[1], J.H. You[1]
[1]Southern Methodist University, Dallas, TX, USA

An acoustic energy harvesting mechanism at low frequency (~200 Hz) using lead zirconate titanate (PZT) piezoelectric cantilever plates placed inside a quarter-wavelength straight-tube resonator has been studied using COMSOL Multiphysics 4.3 and compared with experimental data. When the tube resonator is excited by an incident wave at its acoustic eigenfrequency, an amplified acoustic resonant ...

PA Loudspeaker System Design Using Multiphysics Simulation

R. Balistreri [1],
[1] QSC Audio Products, LLC., Costa Mesa, CA, USA

This paper utilizes lumped circuits equivalent and pressure acoustics to simulate the behavior of a PA loudspeaker in order to improve its design.

Modal Analysis of Functionally-Graded Metal-Ceramic Composite Plates - new

E. Gutierrez-Miravete[1], W. L. Saunders II[2], K. Pendley[3]
[1]Rensselaer at Hartford, Hartford, CT, USA
[2]General Dynamics Electric Boat, Groton, CT, USA
[3]United Technologies - Pratt & Whitney, East Hartford, CT, USA

The determination of the modes of vibration of Functionally Graded-Metal-Ceramic Composite plates is important in practice in order to prevent undesired resonances in structural components. This paper describes the application of COMSOL Multiphysics® software for the determination of the modes of vibration of Aluminum A356-T6Alloy-ZrO2 FG-MCC square plates.

Calculation of Surface Acoustic Waves on a Piezoelectric Substrate using Amazon™ Cloud Computing

U. Vogel [1], M. Spindler [1], S. Wege [1], T. Gemming [1]
[1] Leibniz Institute for Solid State and Materials, Dresden, Germany

In this work, we seek to simulate SAWs for a better understanding and to benchmark the currently available cloud computing possibilities of COMSOL Multiphysics® software. By using the MEMS module we demonstrate 3D models with reduced geometry to achieve principle information about the wavefield. For a benchmark, a high-speed workstation with limited memory (RAM) is compared to the most potent ...