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.

Thermo-Acoustic Analysis of an Advanced Lean Injection System in a Tubular Combustor Configuration

A. Giusti[1], A. Andreini[1], B. Facchini[1], F. Turrini[2], Ignazio Vitale[2]
[1]Department of Energy Engineering, University of Florence, Florence, Italy
[2]Avio, Turin, Italy

In this work a thermoacoustic analysis of a tubular combustor with an advanced lean injection system is presented. The performed analysis is based on the resolution of the eigenvalue problem related to an inhomogeneous wave equation which includes a source term representing heat release fluctuations (the so called Flame-Transfer-Function, FTF) in the flame region. The effect of the mean flow is ...

Design of a Self-Recharging Untethered Mobile Inspection Tool inside a Pipeline

W. Chalgham [1], A. C. Seibi [1],
[1] University of Louisiana at Lafayette, Lafayette, LA, USA

Pipeline inspection tools present some limitations related to power supply which require recharging after each operation. Using batteries or tethered tools make the duration to inspect any pipeline very limited and time consuming. This paper aims at designing a spherical self-recharging untethered mobile ball flowing inside a given pipeline using the COMSOL Multiphysics® software. The ball will ...

Infrasound Assessment of the Roller Compacted Concrete Dam: Case Study of the Portugues Dam in Ponce, PR

H. Diaz-Alvarez [1], V. P. Chiarito [1], S. McComas [1], M. H. McKenna [1],
[1] U.S. Army Engineer Research and Development Center, Vicksburg, MS, USA

The U.S. Army Corps of Engineers is currently investigating the use of infrasound sensors to monitor the health of structures of interest. Infrasound is low-frequency (2-20 Hz) acoustic energy and is capable of propagating many kilometers from the source structure. Large infrastructure, such as dams, bridges, and buildings emit such signals at their natural or driven frequencies of vibration, ...

Friction Factor for Perforated Pipes

D. Neihguk [1], M. L. Munjal [2], A. Prasad [1],
[1] Mahindra & Mahindra Ltd, Chennai, India
[2] 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 [5]. An objective approach presented in [6] 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 ...

Analysis of a Plasma-Mediated Photoacoustic Response From Plasmonic Nanoparticles in Ultrashort Regime

A. Hatef [1], B. Darvish [1], A. Dagallier [2], C. Boutopoulos [2], M. Meunier [2],
[1] Nipissing University, North Bay, ON, Canada
[2] 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 [1]. 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 ...

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

V. Vadde, and B. Lakshmi G
PESIT

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 ...

Feed-forward/Feed-backward Mechanical Amplification in the Mouse Cochlea

J. Soons[1,2], C. Steele[2], S. Puria[2]
[1]Lab of Biomedical physics, University of Antwerp, Antwerp, Belgium
[2]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 ...

Computational Acoustic Attenuation Performance of Helicoidal Resonators

W. Lapka
Poznan University of Technology
Poznan, Poland

This paper concerns the problem of obtaining proper acoustic attenuation performance through computations. COMSOL was used to solve acoustics systems with helicoidal resonators in the frequency domain. Based on the studies of insertion and transmission loss of helicoidal resonators, a high consistency between the results obtained by numerical calculations with experimental measurements was ...

Simulação de um Sistema de Levitação Acústica para Manipulação de Partículas em Ar

M. A. B. Andrade [1], N. Pérez [2], J. C. Adamowski [3],
[1] Instituto de Física, Universidade de São Paulo, São Paulo, SP, Brasil
[2] Centro Universitario de Paysandú, Universidad de la República, Paysandú, Uruguai
[3] Departamento de Engenharia Mecatrônica e Sistemas Mecânicos, Escola Politécnica, Universidade de São Paulo, São Paulo, SP, Brasil

Este trabalho apresenta a simulação numérica de um sistema de levitação acústica para manipulação de partículas em ar. O sistema de levitação consiste de dois transdutores de ultrassom e um refletor de face plana. Através da simulação é calculado o potencial da força de radiação acústica que atua numa esfera. Os resultados da simulação são verificados experimentalmente através da comparação da ...

Phase Decomposition for Loudspeaker Analysis

R. Christensen [1],
[1] GN ReSound A/S, Copenhagen, Denmark

The vibration of an electrodynamic loudspeaker driver causes a resulting sound pressure. For simple pistonic vibration, there is a simple relationship between the vibration and the sound pressure. For complex vibration patterns, however, different parts of the vibrating surface contribute differently to the sound pressure, depending on the position in which the sound pressure is evaluated. A ...