Ici vous trouverez les présentations issues des Conférences COMSOL à travers le monde. Réalisées par des utilisateurs de COMSOL Multiphysics, ces présentations explorent tous les domaines actuels d'innovation. Les applications couvrent pratiquement tous les secteurs industriels et impliquent des phénomènes électriques, mécaniques, fluidiques et chimiques. Utilisez la recherche rapide pour trouver les présentations les plus intéressantes dans votre domaine d'intérêt.

Nondestructive Testing of Composites Using Model Based Design

E. Nesvijski[1]
[1]ACOUSTICS@MBD CONSULTANTS, LLC, Westborough, MA, USA

There is a practical interest among composite materials manufacturers to high-speed accurate non-destructive evaluation (NDE) technology for voids inspection when these voids are natural components of such complex structures like resin insulated layer of double-sided copper-clad laminates. Model based design (MBD) of NDE system is one of principal solutions for voids inspection in such ...

Solving the Inverse Problem of Resonant Ultrasound Spectroscopy on Dumbbell-shaped Compression Samples Using COMSOL Multiphysics®

M. C. Golt[1]
[1]U.S. Army Research Laboratory*, Aberdeen Proving Ground, MD, USA
*Contracted through Dynamic Science, Inc.

The dumbbell geometry is an ideal shape for testing the compressive strength of advanced ceramic materials. This paper details the combined use of COMSOL Multiphysics® and LiveLink™ for MATLAB® for determining the elastic properties of dumbbell-shaped samples by measuring their acoustic resonance frequencies. Degenerate bending modes which are sensitive to inhomogeneities or machining defects ...

Optimization of an Acoustic Waveguide for Professional Audio Applications

M. Cobianchi[1] and R. Magalotti[1]
[1] B&C Speakers S.p.a., Bagno a Ripoli, FI, Italia

In modern live sound reinforcement there is a growing use of line sources, obtained through the stacking of many loudspeakers with properly controlled wavefront shape. Thus the use of waveguides is mandatory in order to modify the shape and size of the wavefront exiting from professional compression drivers. With the help of COMSOL Multiphysics®, we have designed a waveguide featuring an ...

Piezoelectric Buzzer Optimization for Micropumps

A. Garcia[1], A. Marcus[1], F. Tejo[1], C. Precker[1], C. Moreira[2]
[1]Universidade Federal de Campina Grande, Campina Grande, PB, Brazil
[2]Instituto Federal de Alagoas, Maceio, AL, Brazil

Piezoelectric buzzers are low cost devices which can be used successfully as actuators in diaphragm-based micro-pumps. The buzzers are piezoelectric wafers (lead-zirconate-titanate-PZT) that are glued on a brass membrane and they are available within different sizes and thicknesses. For the best performance of a diaphragm pump, it is necessary to have a large displacement of the membrane. This ...

Determination of the Sweet Spot of a Cricket Bat using COMSOL Multiphysics® Software

Y. Mulchand [1], A. Pooransingh [1], R. Latchman [1],
[1] The University of the West Indies, St. Augustine, Trinidad and Tobago

The aim of this paper is to determine the location of the “sweet spot” for a selected cricket bat commonly used in the sport. Knowledge of the “sweet spot” is important in delivering a shot that utilizes the optimal zone of the bat that corresponds to the maximum power of the stroke. A model of the cricket bat was constructed in the Structural Mechanics Module of COMSOL Multiphysics® Software ...

用于中高端扬声器设计的完整仿真分析方法

陆晓 [1], 温周斌 [1], 徐楚林 [1], 岳磊 [1],
[1] 浙江中科电声研发中心,嘉善,中国

扬声器仿真分析方法越来越受到电声企业关注,已成为扬声器设计的重要手段和发展方向。要想设计中高端扬声器,就必须建立一套完整的仿真分析方法。 本文介绍一种基于 COMSOL Multiphysics® 的用于中高端扬声器设计的仿真分析方法。该方法不仅包含了扬声器磁路、振动系统(结构)和声场的耦合分析,还模拟了温度对磁性材料和振动部件材料特性的影响。由于扬声器振动部件材料的粘弹性等特性,因此必须建立更为准确的材料模型。利用 COMSOL Multiphisics 软件丰富的第三方软件接口和二次开发功能,经数据后处理可得到声障板等条件下的声压级、谐波失真和互调失真等。 采用本方法可有效指导中高端扬声器的仿真设计,准确预估扬声器的声压级、谐波失真和温度场等关键指标,对扬声器产品的理解和设计水平亦将达到新的高度。

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 Model of the Insertion Loss Promoted by the Enclosure of a Sound Source

G. F. Greco [1], I. K. S. Hermont [1], B. P. Murta [1], T. B. Romero [1], P. H. Mareze [1], A. Lenzi [2], J. A. Cordioli [2],
[1] Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
[2] Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil

This study aims to develop and validate a finite element numerical model to represent the Insertion Loss (IL) promoted by the enclosure of a sound source. For the validation, a enclosure prototype was built in wood and the IL was measured in laboratory. The idea is to develop an efficient numerical model that would be suitable for enclosure's design and optimization. The problem was modeled ...

Virtual Commissioning of Large Machines with COMSOL Multiphysics® Software

K. Kryniski [1], A. Trangard [1],
[1] ABB Corporate Research, Västerås, Sweden

In addition to using advanced functions built-into the engine of the COMSOL Multiphysics® software, we integrate dynamic properties of rotating components that are measured or pre-computed. Here, it is shown how to integrate fluid-film characteristics and take advantage of post-processing and graphics to present the results to the customers using the Cloud. COMSOL® simulations of rotor-bearing ...

Phonon Tunneling Loss Solver for Micro- and Nanomechanical Resonators

G.D. Cole[1], M. Aspelmeyer[1], and I. Wilson-Rae[2]
[1]University of Vienna, Vienna, Austria
[2]Technical University Munich, Munich, Germany

Micro-and nanoscale mechanical resonators have recently emerged as ubiquitous devices for use in advanced technological applications, for example in mobile communications and inertial sensors, and as novel tools for fundamental scientific endeavors. We report a significant advancement towards understanding and controlling support-induced losses through the demonstration of an efficient numerical ...