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.

Design and Simulation of an Orbiting Piezoelectric MEMS Gyroscope Based on Detection of Phase-Shift Signals - new

S. Gorelick[1], J. R. Dekker[1], B. Guo[1], H. Rimminen[1]
[1] VTT Technical Research Centre of Finland, Espoo, Finland

The feasibility of phase-sensitive detection of angular-rates using bi-directional orbiting piezoresonators suspended by thick annular springs with thin-film aluminium nitride piezoactuators on top of them was investigated. The ring-shaped flexures are more suitable for supporting the orbiting motion due to their angle-dependent spring constant. The response of the orbiting resonators to ...

Considerations Regarding the Design of a Power Ultrasonic Transducer with Flat Rectangular Plate

R. R. Andrés [1], E. Riera [1],
[1] Grupo de Sistemas y Tecnologías Ultrasónicas, ITEFI, CSIC, Madrid, España

There are several industrial applications, like food dehydration, atomization and textile washing among others, that are enhanced by the use of power ultrasonic transducers with flat rectangular plate radiator. These transducers are composed by three main parts, the piezoelectric Langevin type sandwich, the mechanical amplifier, and the extensive plate radiator. Apart from the general ...

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 ...

Modeling the Acoustic Scattering from Objects Buried in Porous Sediment Using COMSOL Multiphysics® Software

A. Bonomo [1], M. Isakson [1],
[1] Applied Research Laboratories, The University of Texas at Austin, Austin, TX, USA

A frequency-domain finite element (FE) technique for computing the acoustic scattering from axially symmetric fluid-loaded structures subject to a nonsymmetric forcing field based on Ref. 1 is extended to poroelastic media and implemented in COMSOL Multiphysics® software. This method allows for the scattering body to consist of any number of acoustic, elastic, and poroelastic domains. The ...

Simplified Finite Element Simulation of a SAW Hydrogen Sensor using COMSOL Multiphysics

N. Krishnan[1], H. Nemade[1,2], and R. Paily[2]
[1]Centre for Nanotechnology, Indian Institute of Technology Guwahati, Assam, India
[2]Department of Electronics and Communication Engineering, Indian Institute of Technology, Assam, India

In this paper, we discuss a simplified finite element method simulation of surface acoustic wave (SAW) delay line hydrogen sensor using COMSOL Multiphysics.  A delay line SAW sensor consists of a transmitting interdigital transducer (IDT) and a receiving IDT separated by a few wavelengths. In this work, the number of degrees of freedom to solve for the SAW delay line sensor model ...

Effects Of The Microstructure Of Fibrous Media On Their Acoustic Properties

C. Peyrega, and D. Jeulin
Center of Mathematical Morphology, Mines ParisTech, Fontainebleau, France

This study is a part of the Silent Wall ANR project, to which the Center of Mathematical Morphology is associated. Its main objective is to build an acoustical and thermal insulating system for buildings, composed of fibrous materials. The material is composed of two phases: the fibrous network and the air surrounding it. At the microscopic scale the absorption of the acoustic wave is mainly ...

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 ...

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 ...

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 ...

Development of a Package for a Triaxial High-G Accelerometer Optimized for High Signal Fidelity

R. Langkemper [1], R. Külls [1], J. Wilde [2], S. Nau [1], S. Schopferer [1],
[1] Fraunhofer-Institut für Kurzzeitdynamik, Ernst-Mach-Institut, EMI, Freiburg, Germany
[2] Albert-Ludwigs-Universität Freiburg, Institut für Mikrosystemtechnik, Freiburg, Germany

Acceleration is an important quantity to be measured in high-speed dynamics. A new piezoresistive sensor for the measurement of high-amplitude, short-duration transient accelerations of up to 100,000 g has been developed at the Fraunhofer EMI. Its figure of merit (sensitivity x resonance frequency²) is about one order of magnitude higher than that of comparable state-of-the-art sensors. ...