Here you will find presentations given at COMSOL Conferences around the globe. The presentations explore the innovative research and products designed by your peers using COMSOL Multiphysics. Research topics span a wide array of industries and application areas, including the electrical, mechanical, fluid, and chemical disciplines. Use the Quick Search to find presentations pertaining to your application area.

Modelling the Wall Vibrations of Brass Wind Instruments

V. Chatziioannou, and W. Kausel
Institute of Music Acoustics
University of Music and Performing Arts
Vienna, Austria

The vibration of the walls of brass wind instruments has been a subject of study in the field of musical acoustics throughout the last decades. The amplitude of such vibrations, stimulated by the oscillating air pressure inside the instrument bore, is very small compared to the dimensions of the instrument. However, it has been recently shown that at the flaring regions of the bell of brass ...

Numerical Modelling of Wave Propagation in Particulate Composites

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. ...

Finite Element Modeling of Ultrasonic Transducers for Polymer Characterization

S. De Paolis[1], F. Lionetto[1], and A. Maffezzoli[1]

[1]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 ...

Acoustic Emission Simulation for Online Impact Detection

C. Yang, M. A. Torres-Arredondo, and C.-P. Fritzen
Institute of Mechanics and Control Engineering
University of Siegen
Siegen, Germany

Impact monitoring has been extensively studied by several researchers and it has been shown that damage extent can be correlated with the impact magnitude. In order to make the process cost-effective, simulation of the impact has been performed, to get the big training data set from modeling. The structural dynamic responses captured by PZT transducers due to impact events are recorded from ...

A Finite Element Model of Shear Wave Propagation Induced by an Acoustic Radiation Force Impulse

R. De Luca[1,2], J. Fromageau[1], H.W. Chan[1], F. Marinozzi[2], J. Bamber[1]
[1]Institute of Cancer Research and Royal Marsden Hospital, Sutton, England, United Kingdom
[2]Sapienza University of Rome, Dept. of Mechanical and Aerospace Engineering, Rome, Italy

Shear wave elastography is an innovative technique used in combination with the traditional ultrasound imaging to improve the specificity of cancer imaging. A two-dimensional finite element model (FEM), composed of realistic boundary conditions, was developed in COMSOL Multiphysics® to simulate the propagation of shear waves induced by an acoustic radiation force impulse (ARFI) in isotropic, ...

Characterization of a Tonpilz Transducer and Performance Analysis for a MEMS-Transducer Array

V. Vadde, and B. Lakshmi G

In this paper, we develop and analyze a standard piezoacoustic Tonpilz-transducer model for underwater acoustics in Comsol by addressing the attendant piezoelectric and pressure acoustic multiphysics phenomena. Transducer properties that are studied and characterized are the center frequency, bandwidth, linearity, sensitivity, and noise figure. In an effort to miniaturize the transducer, a ...

Designing Materials for Mechanical Invisibility Cloaks

P. Olsson[1], F. Larsson[1], A. Khlopotin[1], S. Razanica[1]
[1]Chalmers University of Technology, Gothenburg, Sweden

In solid mechanics, there is considerable interest in achieving “invisibility”. The applications in mechanics include protection of structures and parts of structures from potentially harmful transient waves and steady state vibrations. A suggested large scale application is that protection against seismic waves from earthquakes could be achieved by using cloaking to re-route the waves around ...

Mean Flow Augmented Acoustics in Rocket Systems - new

S. Fischbach[1]
[1]NASA Marshall Space Flight Center / Jacobs ESSSA Group, Huntsville, AL, USA

Combustion instability in solid rocket motors and liquid engines has long been a subject of concern. Recent advances in energy based modeling of combustion instabilities require accurate determination of acoustic frequencies and mode-shapes. Of particular interest is the acoustic mean flow interactions within the converging section of a rocket nozzle, where gradients of pressure, density, and ...

Guided Wave in Engineering Structures Using Non-Contact Electromagnetic Acoustic Transducers: A Numerical Approach for the Technique Optimisation

S. Soua[1], A. Raude[1], and T-H. Gan[1]
[1]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 ...

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 ...