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.
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Simulação de um Sistema de Levitação Acústica para Manipulação de Partículas em Ar

M. A. B. Andrade [1], N. Pérez [2], J. C. Adamowski [3],
[1] Instituto de Física, Universidade de São Paulo, São Paulo, SP, Brasil
[2] Centro Universitario de Paysandú, Universidad de la República, Paysandú, Uruguai
[3] Departamento de Engenharia Mecatrônica e Sistemas Mecânicos, Escola Politécnica, Universidade de São Paulo, São Paulo, SP, Brasil

Este trabalho apresenta a simulação numérica de um sistema de levitação acústica para manipulação de partículas em ar. O sistema de levitação consiste de dois transdutores de ultrassom e um refletor de face plana. Através da simulação é calculado o potencial da força de radiação acústica que atua numa esfera. Os resultados da simulação são verificados experimentalmente através da comparação da ...

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 ...

Guided Wave in Engineering Structures Using Non-Contact Electromagnetic Acoustic Transducers: A Numerical Approach for the Technique Optimisation

S. Soua[1], A. Raude[1], and T-H. Gan[1]
[1]NDT Technology Group, TWI Ltd, Cambridge, United Kingdom

There are over 10 million kilometers of pipes and pipelines around the world that carry hazardous fluids and gases. Fluids include oil, oil products, chemicals such as solvents, caustics, acids, corrosives and combustibles often at high pressure and temperature. These pipes are susceptible to corrosion if they are not protected properly by the environment or the contents. Inspection of pipes is ...

Vibration Analysis of Rectangular Perforated Plates by COMSOL Multiphysics® Software

B. Raghavendra[1]
[1]SRM University & BITS Pilani University, Chennai, Tamil Nadu, India

Vibration analysis of perforated plates is extremely important when designing structures where resonance is the possible mode of failure. This paper deals with the vibration analysis of rectangular perforated plates with three different types of perforations. Vibration analysis is to be carried out by both COMSOL Multiphysics® Software and Experimental set-up. The applications of perforated ...

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 ...

Electro-acoustic Coupling in Nematic Liquid Crystals

G. Rosi[1], L. Teresi[1], A. DiCarlo[1], and F. dell'Isola[2]
[1]LaMS - Università degli Studi Roma Tre, Roma, Italy
[2]Università degli Studi di Roma "La Sapienza", Roma, Italy

Liquid crystals - as all liquids - are generally modelled as incompressible media. In fact, mass-density changes occurring in these mesophases are minuscule and inconsequential in most regimes of interest. However, liquid crystals exhibit also phenomena that call for a more refined theory. In particular, it is experimentally well established that the Fréedericksz transition - i.e., the sudden ...

Underwater Flow Noise Simulation

S. H. Abadi [1], A. T. Lim [1],
[1] University of Washington, Bothell, WA, USA

Underwater acoustics is an area that studies the sound propagation in water and the interactions with other objects and water boundaries. There are many technologies available for acoustic exploration of the ocean. Underwater vehicles are robots used in ocean sciences that travel underwater autonomously and can tow a hydrophone as a mobile sensor to record sound. The turbulent flow induced by ...

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 ...

Simulating the Response of Planar Photonic Structures Under the Strain of Surface Acoustic Waves

O. D. D. Couto Jr. [1], A. C. T. Covacevice [1],
[1] Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, Campinas, SP, Brazil

In this contribution, we simulate the optical response of piezoelectric planar optical microcavities (POMCs) under the modulation introduced by a propagating surface acoustic wave (SAW). The physical picture of the model is shown in Figure 1. A metallic interdigital transducer (IDT) is placed on the sample surface and, via inverse piezoelectric effect, is responsible for the generation of SAWs ...

PCCP Profiling and Tube Wave Analysis of WRE Signal

N. Chowdhury[1], Z. Liao[2], and L. Zhao[1]
[1]Department of Electrical & Computer Engineering, Ryerson University, Toronto, ON, Canada
[2]Department of Architectural Science, Ryerson University, Toronto, ON, Canada

Acoustic wave propagation due to the breakage or slippage of reinforced wire in water-filled prestressed concrete cylinder pipe (PCCP) attracts interest in non-destructive pipe testing. Current practice of acoustic emission (AE) detection and wire-break related events (WRE) recognition is based on field data analysis. This work deals with the theoretical investigation of WRE signal from ...