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.

Analyzing Muffler Performance Using the Transfer Matrix Method 

K. Andersen
Dinex Emission Technology A/S, Middelfart, Denmark

Exhaust noise must meet legislation targets, customer expectations and cost reduction which call for design optimization of the exhaust systems in the design phase. One solution is to use 3 dimensional linear pressure acoustics and calculate the transfer matrix of the muffler. The transfer matrix is the basis for calculating either the insertion loss or transmission loss of a muffler. The 3D ...

Modeling of a Jecklin Disk for Stereophonic Recordings

G. McRobbie[1]
[1]University of the West of Scotland, Paisley, Renfrewshire, UK

The Jecklin Disk is a sound absorbing disk placed between two omnidirectional microphones. It is used to recreate some of the frequency-response, time and amplitude variations human listeners’ experience, but in such a way that the recordings also produce a useable stereo image through loudspeakers. This paper presents a finite element model able to simulate the effects on sound propagation ...

Numerical Simulation of Phonon Dispersion Relations for Phononic Crystals

G. Zhu[1], E.M. Dede[1]
[1]Toyota Research Institute of North America, Ann Arbor, MI, USA

In previous work, a two-dimensional (2D) model was carried out to simulate the phononic band structure of a phononic crystal with square lattice structure, but this model did not account for the out-of-plane phonon dispersions [1]. In fact, for 2D films used for coating materials, it is more interesting to understand their cross-plane properties. In this work, the phonon dispersion relation of ...

MEMS Electrostatic Acoustic Pixel

A. Arevalo [1], D. Conchouso [1], D. Castro [1], I. G. Foulds [2],
[1] Computer, Electrical, & Mathematical Sciences & Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
[2] The University of British Columbia, School of Engineering, Vancouver, BC, Canada

The growth of the electronics industry demand better components for the electronic systems. Such components need to be improve to keep up with the evolution of the digital era. The loudspeaker design has not been changed for almost a century [1-5]. The acoustic transducer is the last analogue component needed for a true digital audio system. We want to validate the feasibility of using an ...

Improved Perfectly Matched Layers for Acoustic Radiation and Scattering Problems

M. Zampolli[1], N. Malm[2], and A. Tesei[1]
[1]NURC NATO Research Centre, La Spezia, Italy
[2]COMSOL AB, Stockholm, Sweden

Perfectly matched layers (PML) are an efficient alternative for emulating the Sommerfeld radiation condition in the numerical solution of wave radiation and scattering problems. The key ingredient of the PML formulation is the complex scaling function, which controls the anisotropic damping of the PML. The objective of this study is to propose a modified complex scaling function capable of ...

Modeling Acoustic Interface Wave Dispersion Using COMSOL Multiphysics®

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

Measuring geoacoustic parameters of underwater sediments is important for accurate modeling of underwater acoustic propagation. While the density and compressional wave speeds can be directly measured in sediments, shear wave speeds are difficult to measure because they are highly attenuated. However, shear wave speeds can be indirectly determined through measurement of Scholte interface wave ...

Calculation of Surface Acoustic Waves on a Piezoelectric Substrate using Amazon™ Cloud Computing

U. Vogel [1], M. Spindler [1], S. Wege [1], T. Gemming [1]
[1] Leibniz Institute for Solid State and Materials, Dresden, Germany

In this work, we seek to simulate SAWs for a better understanding and to benchmark the currently available cloud computing possibilities of COMSOL Multiphysics® software. By using the MEMS module we demonstrate 3D models with reduced geometry to achieve principle information about the wavefield. For a benchmark, a high-speed workstation with limited memory (RAM) is compared to the most potent ...

Simulation of Piezoelectric Nanofibers for Harvesting Energy Applications - new

S. Rouabah[1], A. Chaabi[1]
[1]Electronics Department, Constantine University, Constantine, Algeria

In this work, we have taken a model which is simulated using COMSOL Multiphysics®. It was used as a tool to design, characterize and to simulate an example which is nanofibers based piezoelectric energy generators. The results are compared with other available sources but using with another materials. After applying a pressure on the top of surface of nanogenerator, the output parameters ...

Modeling and Simulation of Dual Application Capacitive MEMS Sensor - new

A. Ravi[1], R. Krishna[1], J. Christen[1]
[1]Arizona State University, Tempe, AZ, USA

Capacitive MEMS sensors offer high spatial resolution, sensitivity and good frequency response. In this paper, we present a circular membrane capacitive MEMS device that finds use both as capacitive micromachined ultrasonic transducer (CMUT) and pressure sensor. The MEMS device is first designed and simulated to work as a CMUT operating at about 5 MHz frequency. The device can also function as a ...

Acoustical Design of Stethoscope for Improved Performance

C. Thiagarajan[1], Gururajan R.[2], A. H. Baig[2], Prema S.[3]
[1]ATOA Scientific Technologies Pvt Ltd, Whitefield, Bangalore, Karnataka India
[2]University of Southern Queensland, Toowoomba Qld 4350, Australia.
[3]RMK Engineering College, Chennai, Tamil Nadu, India

Stethoscope is in use for more than 200 years for medical diagnostics, especially for auscultation. Recently, the unprecedented growth in mobile technology revived the use of stethoscope for Telehealthcare. Digital or electronic stethoscopes are increasingly researched for use in Telehealthcare. This paper mainly focuses on the acoustical and multiphysics design aspects of the stethoscope for ...