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.

Acoustic Wave Propagation in Water Filled Buried Polyethylene Pipes - new

T. Graf[1], T. Gisler[1], P. Sollberger[1], O. Schaelli[1]
[1]School of Engineering and Architecture, Lucerne University, Horw, Switzerland

Axisymmetric acoustic waves propagating along buried water pipes have been investigated by FEM and experimentally. Universal dispersion relations of the fundamental mode were obtained as a function of the standard dimension ratio SDR and of the material surrounding the pipe (soil, air). At low frequency there exists little dispersion and the “dc” phase velocity of the leak noise is independent ...

Scale-up Design of Ultrasound Irradiator for Advanced Oxidation Process (AOP) Using COMSOL Multiphysics® Simulation

Z. Wei[1]
[1]The Ohio State University, Columbus, OH, USA

Ultrasound is a promising green technology for the advanced oxidation process (AOP) since it adds no chemicals to the treated water. In this paper, COMSOL Multiphysics® was used as a tool to design and characterize an ultrasound irradiator with multi-stepped configuration, which aims to overcome disadvantages of typical irradiators and to enhance contaminant removal in large-scale water ...

Simulation of a New PZT Energy Harvester with a Lower Resonance Frequency Using COMSOL Multiphysics® - new

H. Elbahr[1], T. Ali[1,2], A. Badawi[1], S. Sedky[1]
[1]Zewail City of Science and Technology - Cairo, Cairo, Egypt
[2]Cairo University, Cairo, Egypt

Energy harvesting from environmental vibration nowadays is feasible because of natural oscillations like that caused by air or liquid flow and by exhalation or the heartbeat of a human body. This vibration frequency is typically low (in order of less than 1 kHz). Accordingly, low-frequency vibration based energy harvesting systems are an important research topic; these systems can be used for ...

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 ...

Simulation of Impact Damage in a Composite Plate and Its Detection

V. Pavelko[1], I. Pavelko[1], M. Smolyaninovs[1], H. Pffeifer[2], M. Wevers[2]
[1]Riga Technical University, Riga, Latvia
[2]Catholic University Leuven, Leuven, Belgium

A problem of damage prediction in aircraft structure and its non-destructive evaluation is very important for aircraft structural health assessment. The analysis of the features of direct impact of thin-walled laminate component of aircraft was performed by COMSOL Multiphysics software. Mainly the GFRC and CFRC laminates were selected in form either thin separate plate or sandwich structure. The ...

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 ...

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 ...

Prediction of Noise Generated by Electromagnetic Forces in Induction Motors - new

M. K. Nguyen[1], R. Haettel[2], A. Daneryd[2]
[1]KTH, Stockholm, Sweden
[2]ABB Corporate Research,Västerås, Sweden

Induction motors, as any other industrial products, have to comply with various requirements on noise levels. Therefore, it is essential to use an appropriate prediction tool to verify and optimize the design of an induction motor with respect to the acoustic performances. The paper will focus on the prediction of the magnetic noise generated and radiated by a specific motor. The challenge is ...

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 ...