Aqui você encontrará apresentações realizadas nas Conferências de Usuários COMSOL de todo o mundo. As apresentações englobam pesquisas e produtos inovadores feitas por engenheiros e cientistas usando o COMSOL Multiphysics. Os tópicos abramgem uma grande gama de indústrias e aplicações, como elétrica, mecânica, escoamento e química. Use a função de busca "Quick Search" para encontrar apresentações na sua área de interesse.

High-Intensity Piezo-Ceramic Ultrasonic Transducer with Mechanical Amplifier and Radiation Plate

A. van Wijhe[1], W. de Jong[1]
[1]Process & Energy, 3mE, TU Delft, The Netherlands

A COMSOL Multiphysics® model was made to design a mechanical amplifier and radiation plate for the emission of high intensity 40.5 kHz ultrasound to air by means of a Langevin type transducer usually applied in cleaning baths for example. In this work, ultrasonic irradiation is aimed at acting on flue gas containing fine particulate matter to realize a shift to higher effective particle sizes as ...

Predication of Acoustical Dissipation in Large Irregular Cavities by Helmholtz Solver

F. Mbailassem [1], Q. Leclere [1],
[1] LVA - INSA de Lyon, France

This paper introduces an efficient model to describe energy dissipation in acoustic. When the propagation domain has hard wall boundary conditions only viscous and thermal losses happen and are completely described by the so-called Full Linearized Navier-Stokes model (FLNS) which is implemented in thermoacoutics interface using the COMSOL Acoustics Module. This model defined by a set of ...

Simulation of Acoustical Transfer Paths for Active Noise Control

L. Fromme [1], J. Waßmuth [1], D. Wehmeier [1],
[1] Bielefeld University of Applied Sciences, Bielefeld, Germany

The knowledge of the acoustical transfer paths in active noise control systems is very important for the performance of the system. Unfortunately, simulation is challenging since even simple configurations require comprehensive experience in physics and modeling. Two test setups were chosen for basic investigations on modeling, simulation and validation. The first results presented here are ...

Computational Modeling of Wave Propagation in a Geophysical Domain

J. McKenna[1], M. McKenna[1], S. Yushanov[2], J. Crompton[2], and K. Koppenhoefer[2]
[1]U.S. Army Engineering Research and Development Center
[2]ACES of Columbus, LLC, Columbus, OH, USA

The propagation of shear (S) and compression (P) waves within the earth allows geologists to track seismic events and to identify subterranean structure. This work shows the strong effect of including the variation of wave speed through the top thirty meters of the earth. By including this variation in material properties, the wave arrival time and frequency content agree with experimental data. ...

Finite Element Analysis of Photoacoustic Response from Gold Nanoparticle

Y. Davletshin[1], J. C. Kumaradas[1]
[1]Ryerson University, Toronto, ON, Canada

Photoacoustic (PA) imaging has matured into a clinical modality for tissue imaging and functional cancer cell research. It uses a pulsed laser to irradiate a region and generate a thermally-induced acoustic pressure wave that can be collected by an ultrasound transducer. The optical absorption/PA contrast of the region of interest can be enhanced by the use of plasmonic nanoparticles. The ...

Study & Modeling of 'Acoustic Matching Layers' for Ultrasound Imaging Probes Through Pulse-Echo FEM Simulation - new

L. Spicci[1]
[1]Esaote SpA, Florence, Italy

Ultrasound Imaging probes are specific devices that require a very detailed design of acoustic impedance match for the stack of layers that form the probe head (1,3). These are typically made of silicone rubber, special epoxy resins, polyurethanes and, of course, piezoelectric materials. The acoustic impedance, measured in Rayls, have to be matched similarly to an electric circuit (2), from a ...

Analysis of the Acoustic Response of a Railroad Bridge

K. Koppenhoefer[1], S.Yushanov[1], and M.H. McKenna[2]

[1]AltaSim Technologies, LLC, Columbus, Ohio, USA
[2]U.S. Army Engineering Research and Development Center

Aging infrastructure requires frequent inspections to assess their structural integrity. However, the large amount of existing infrastructure, and the distance between these structures present significant challenges to inspectors. Acoustics-based technologies represent a simple, and relatively inexpensive, technique to monitor the integrity of a structure. To develop these techniques, designers ...

Acoustic-Structure Interaction Simulation of a Differential Phase Sensor - new

J. H. Lee[1]
[1]Department of Mechanical Engineering, American University of Sharjah, Sharjah, UAE

The idea of application as a hearing device based on a parasitoid fly, Ormia ochracea has been studied extensively recently. This paper addresses another possible application as an underwater directional sensor. In order to study the feasibility of the application, it is necessary to investigate the feasibility of the underwater application of the directional sensor based on the hearing ...

A MEMS Condenser Microphone for Consumer Applications

S. L. Pinjare, V. S. Nagaraj, S. N. Savitha, S. Kesari, M. S. Sagar, and K. R. Roshan
Nitte Meenakshi Institute of Technology

The MEMS microphone is also called microphone chip or silicon microphone. The pressure sensitive diaphragm is etched directly into a silicon chip by MEMS techniques and is usually accompanied with integrated preamplifier. Most MEMS microphones are variants of the condenser microphone design. The MEMS microphone has been successfully fabricated and tested in an anechoic chamber. The microphone ...

The Effect of Resistance on Rocket Injector Acoustics

C. J. Morgan [1], S. R. Fischbach [1],
[1] Jacobs ESSSA Group, NASA Marshall Space Flight Center, Huntsville, AL, USA

This study evaluates the effect of injector resistance on the mode shapes and complex eigenfrequencies of an injector/combustion chamber system by defining a high Mach-flow, potential flow form of the convective wave equation in the Coefficient Form PDE Mathematics interface. Background steady-state flow conditions are determined through a NASA Marshall Space Flight Center in-house fluid ...