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.

Ultrasound-assisted Microfluidic Devices: Insights and Optimization of Sono-microreactors

F. J. Navarro-Brull [1], P. Poveda [2], J. Ramis [2], R. Gómez [1],
[1] Departament de Química Física, Universidad de Alicante, Alicante, Spain
[2] Departament de Física, Enginyeria de Sistemes i Teoria del Senyal, Universidad de Alicante, Alicante, Spain

Possible drawbacks of microreactors are inefficient reactant mixing due to the predominance of laminar flow and clogging (when solid-forming reactions are performed or solid catalyst suspensions are used). Ultrasound has been successfully implemented not only to prevent these problems but also for its well-known mixing and particle-dispersion effects. Several configurations have been used for ...

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 ...

Increasing Heat Transfer in Microchannels with Surface Acoustic Waves - new

S. Berry[1]
[1]Massachusetts Institute of Technology: Lincoln Laboratory, Lexington, MA, USA

In this numerical study, surface acoustic waves (SAWs) are evaluated as a potential disruptive flow technology for enhancing heat transfer in microchannels. Using COMSOL Multiphysics® software, the physics governing acoustics, single-phase-fluid flow and heat transfer are coupled. The results show that acoustic streaming can disrupt the bulk fluid flow, creating rotating vortices within the ...

Designing a Smart Skin with Fractal Geometry

S. Ni, C. Yang Koh, S. Kooi, and E. Thomas
Institute for Soldier Nanotechnologies
Dept. of Materials Science and Eng.
Cambridge, MA

Recently, the concepts of fractal geometry have been introduced into electromagnetic and plasmonic metamaterials. With their self-similarity, structures based on fractal geometry should exhibit multi-band character with high Q factors due to the scaling law. However, there exist few studies of phononic metamaterials having fractal geometry. COMSOL is used to investigate vector elastic and ...

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 ...

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 ...

Design Of Acoustic Metamaterials Based On The Concept Of Dual Transmission Line

A-S.Moreau[1], H.Lissek[1], and F. Bongard[2]
[1]Ecole Polytechnique Fédérale de Lausanne, Switzerland
[2]JAST SA, Antenna Systems, Lausanne, Switzerland

In this context, a one-dimensional acoustic transmission line, exhibiting metamaterial properties, is presented. It is composed of an acoustic waveguide, periodically loaded with membranes having the function of series capacitances, as well as transversally connected open channels (denoted stubs) having the function of shunt inductances. A validation of the transmission line design is made ...

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 ...

Modeling and Testing of Carbon-Fiber Doubly-Resonant Underwater Acoustic Transducer

A. Morozov[1]
[1]Teledyne Technologies Inc., Falmouth, MA, USA

This paper describes the COMSOL Multiphysics® simulation and the test of a low-frequency (500Hz) sound source for long-range acoustic communications. This design uses innovative carbon-fiber composite materials.To meet the demand for the frequency range the doubly resonant organ pipe resonator was suggested. A multi-resonant system usually needs a precise, complicated adjustment of its ...

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 ...