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.

Designing Materials for Mechanical Invisibility Cloaks

P. Olsson[1], F. Larsson[1], A. Khlopotin[1], S. Razanica[1]
[1]Chalmers University of Technology, Gothenburg, Sweden

In solid mechanics, there is considerable interest in achieving “invisibility”. The applications in mechanics include protection of structures and parts of structures from potentially harmful transient waves and steady state vibrations. A suggested large scale application is that protection against seismic waves from earthquakes could be achieved by using cloaking to re-route the waves around ...

Numerical Study on the Mechanism of Interface Debonding Detection for CFST with PZT

H. Chen [1], J. Li [1], S. Xia [2],
[1] Hunan University, Changsha, Hunan, China
[2] Xi'an Jiaotong University, Xi'an, Shaanxi, China

Introduction In order to understand the detection mechanism of the PZT based nondestructive testing (NDT) technology for interface debonding of CFSTs, numerical simulation on a multi-physical model composed of surface-mounted PZT patches and CFST structural member is established in COMSOL Multiphysics®. The stress propagation process and the electrical signal output of an embedded PZT patch as ...

Harmonic Simulation of Viscoelastic Polymer Microcantilever for Electrostrictive Energy Harvesters

N. Alcheikh[1], C. Ayela[1], I. Dufour[1]
[1]Univ. Bordeaux, IMS Lab, Pessac, France.

Electrostrictive polymers have been of significant interest over the last years for energy harvesting. Principle is based on the conversion of a mechanical deformation into electricity. The stored energy basically depends on the mechanical strain induced into an electrostrictive polymer by the mechanical resonant vibration of a microcantilever supporting the electrostrictive layer. In this work, ...

Nondestructive Testing of Composites Using Model Based Design

E. Nesvijski[1]

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 ...

Thermal Analysis of a Piezo-Disk Ultrasound Probe

L. Spicci[1], M. Cati[1]
[1]Esaote, Firenze, Italy

Ultrasound imaging probes are widely used for several types of diagnosis applications. In the present work we focus our attention on a disk-type probe, which is widely used in CW and PW operating conditions. In particular we present a 2D-axial symmetry FEM for the probe, capable to predict both the operative temperature values at different driving signal frequencies, both the heating dynamics. ...

Comparison of an Analytical and Numerical Solution for the Landmine Detection Problem

M. Mattingly[1], K. McIlhany[2], and R. Malek-Madani[3]

[1]Applied Research Laboratory, The Pennsylvania State University, University Park, PA, USA
[2]Physics Department, United States Naval Academy, Annapolis, MD, USA
[3]Mathematics Department, United States Naval Academy, Annapolis, MD, USA

Acoustic landmine detection is accomplished using a loud speaker as an airborne source to generate low-frequency waves that enter the soil at a certain incident angle. At a specific frequency, the landmine will "vibrate" at resonance, imparting a certain velocity on the soil particles above it that is detected by a scanning Laser Doppler Vibrometer system. The ability to mathematically predict ...

Linear Water Wave Propagation around Structures

L. Martinelli, and A. Lamberti
Universita di Bologna, Italy

Objective of this contribution is to show how to implement the Mild Slope Equations with COMSOL Multiphysics. These equations are commonly used to study the propagation of waves in harbors. Some interesting features are presented, namely the use of weak terms (used for the modelling of the source term); the evaluation of a smooth phase gradient from the complex dependent variable; a robust ...

Modeling Acoustic Waveguides for Ear Impedance Measurements

R. Sisto[1], L. Cerini[1], D. Mambro[2], A. Moleti[2], F. Sanjust[1]
[1]INAIL Research, Monteporzio Catone, Italy
[2]Università di Roma, Tor Vergata, Italy

The otoacoustic emissions (OAEs) are acoustic signals emitted by the inner ear as a consequence of the activity of a nonlinear feedback mechanism capable of amplifying the signal near to the hearing threshold level. The otoacoustic emissions can be used as an acoustic imaging of the cochlear functionality. They are used in clinics for screening purposes but due to the extreme variability ...

Acoustic-Structure Interaction Modeling of Piezoelectric Transducer in Fluid Medium

V.M. Acosta[1], E. Riera[1], G. Rodriguez[1], A. Pinto[1], A. Cardoni[2], J.A. Gallego-Juárez[1]
[1]Power Ultrasonics Group, CSIC, Serrano, Madrid, Spain
[2]Pusonics, Arganda del Rey, Madrid, Spain

This work describes the design methodology and development of piezoelectric transducers for applications in fluids with COMSOL_Multiphysics. In these linear models for the acoustic-structure interaction approximate numerical solutions have been obtained. In order to perform the calculations, simplifications are only valid for low-power sound waves. Numerical modeling of piezoelectric transducers ...

MEMS-based Handy Fuel Adulteration Detection Device

Anumeha Dwivedi[1], Dr. R. Dey[2]
[1]BITS Pilani K.K. Birla Goa Campus, Goa, India
[2]Associate Professor, BITS Pilani K.K. Birla Goa Campus, Goa, India

Adulteration of automobile fuels, especially petrol and diesel is a rampant malpractice in India. With the rising prices of fuel and the subsidy on kerosene, getting away with even 10-15% adulteration is immensely profitable.To check adulteration effectively, it is necessary to monitor the fuel quality at the distribution point itself. The equipment for this purpose should be handy and the ...