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.
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Numerical Study on Shear Horizontal Electromagnetic Acoustic Transducers for Generation of Ultrasonic Guided Waves for Absorber Tubes used in Concentrated Solar Plants - new

L. Cheng[1], A. Mohimi[1], M. Kogia[1], V. Kappatos[1], C. Selcuk[1], T.-H. Gan[1]
[1]Brunel Innovation Centre, Brunel University, Uxbridge, UK

Absorber tubes are one of the most critical components of parabolic trough Concentrated Solar Plants, which is very likely get damaged such as crack and mass loss. Therefore, the monitoring of their structural health via Non-Destructive Testing (NDT) techniques is regarded as essential for preventing them from being significantly defective and thereby reducing maintenance cost. Non-contact ...

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 ...

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 ...

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 ...

Simulating Acoustic Combustion Chamber Eigenmodes to Facilitate Combustion Stability in Rocket Engines

R. Kaess [1], J. Braun [1],
[1] Airbus Safran Launchers, Ottobrunn, Germany

Airbus Safran Launchers is the market leader in Space Launch services. Rocket engines are among the most powerful machines that exist. The core of the rocket engine is the combustion chamber where in the case of liquid propellant rocket engines, fuel and oxidizer are injected, mixed and burnt and where, consequently, the energy release takes place. The hot combustion gases are accelerated in a ...

Optimization of Acoustic Silencer for the Screw Compressor System - new

M. Swamy[1], L. J. van Lier[1], J. Smeulers[1]
[1]TNO, Delft, The Netherlands

In one of the screw compressor system, designed silencer was not optimal. A great challenge was the large variation in operating conditions, especially the variation of the molecular weight of the gas. There was need to optimize the silencer. This paper describes the acoustic modelling tools to optimize the acoustic performance of the silencer. Optimization steps carried out are based on the ...

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 ...

Developing Solutions to Tonal Noise from Wind Turbines Using COMSOL Multiphysics® Software

J. M. Stauber [1], B. A. Marmo [1],
[1] Xi Engineering Ltd, Edinburgh, United Kingdom

Tonal noise from wind turbines can have effects on neighboring residences and its emission can result in strong regulatory penalties that can include the closure of wind farms. The authors present a model of a new broadband damping approach where containers filled with EniDamp™, an Advance Particle Damping (APD) material. The containers, so-called APD pods, are magnetically fixed to wind ...

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 ...

Design and Implementation of Multichannel Piezoelectric Acoustic Sensor

R. S. Hallikar [1], S. Munshi [1], M. U. Kumari[1], K. Padmaraju[2],
[1] R. V. College of Engineering, Bengaluru, Karnataka, India
[2] JNTU Kakinada, Kakinada, Andhra Pradesh, India

This paper concentrates on developing a self-contained cochlea whose performance is at par with natural hearing. The Artificial Basilar Membrane (ABM) design is done in such a manner so as to get a performance similar to the natural hearing. Finite element analysis was done with the help of COMSOL Multiphysics software. Two materials, Polyvinylidene fluoride (PVDF) and lead zirconate titanate ( ...