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.

Shape, Convection and Convergence

R. Pryor
Pryor Knowledge Systems, Inc., Bloomfield Hills, MI, USA

COMSOL Multiphysics software, when properly configured, can readily solve modeling problems in the laminar flow regime using the standard Navier-Stokes equations or in the fully turbulent flow regime using the kappa-epsilon model. Failure to solve a particular model is typically manifested by instability in the calculation and a failure of the model to converge. This paper presents a new ...

Modeling of Silicon Piezoresistive Pressure Sensor: Application to Prevent Some Diabetes Complications

F. Kerrour[1], A. Beddiaf[1], M. Benabbas-Marir[1]
[1]MODerNa Laboratory, University Mentouri, Constantine, Algeria

Several analytical solutions describing the mechanical behavior of a silicon micro membrane deflection, perfectly embedded and subjected to a uniform and constant pressure have been proposed. The obtained results are compared with those obtained by using COMSOL software for a rectangular diaphragm deflection. COMSOL Multiphysics is powerful software for solving problems based on partial ...

Actively Controlled Ionic Current Gating In Nanopores

G. Zhang[1], S. Bearden[1]
[1]Clemson University, Clemson, SC, USA

It is necessary to understand and control nanopore behavior in order to develop biosensors for a variety of applications including DNA sequencing. The fluidics of nanopore devices we fabricated exhibits a range of interesting phenomena, such as enhanced conductance and current rectification. By electrically biasing nanopores, we were able to actively control the nanopore conductance in real time ...

Viscous damping of a periodic perforated MEMS microstructure when the Reynolds’ equation cannot be applied: Numerical simulations

D. Homentcovschi[1], and R.N. Miles[1]
[1]Department of Mechanical Engineering, SUNY Binghamton, NY

This paper develops a computational model for determining the total damping coefficient for a unit cell of a MEMS microscale device containing a repetitive pattern of holes. The basic cell of the microstructure is approximated by an axi-symmetric domain and the velocity and pressure fields are determined from solutions of the Navier-Stokes equations using the finite element software package ...

Magnetic Ratchet

A. Auge, F. Wittbracht, A. Weddemann, and A. Hütten
Department of Physics, University of Bielefeld, Germany

Transport phenomena in spatially periodic magnetic systems, in particular the directed transport of magnetic beads in a so called magnetic ratchet (Brownian motor) are considered. Simulations are carried out to test and optimize this system, where the Smoluchowski equation with flux terms for the magnetic and gravitational force is used. Furthermore, experiments are carried out to verify the ...

Design and Simulation of MEMS-based Piezoelectric Accelerometer

Siram Sai Krishna[1], Nuti Venkata Subrahmanya Ayyappa Sai[1], Dr.K.Srinivasa Rao[2]
[1]Lakireddy Bali Reddy College of Engineering, Mylavaram, Andhra Pradesh, India
[2]Professor & HOD, Dept. of Electronics and Instrumentation Engineering, Lakireddy Bali Reddy College of Engineering, Mylavaram, Andhra Pradesh, India

The Micro electro mechanical systems (MEMS) technology provides us a platform to interface between mechanical and electrical components. In this paper, we have designed MEMS accelerometer based on piezoelectric property, and simulated using COMSOL Multiphysics®. The design, which has PZT kept in the annular diaphragm, provides good sensitivity. When this accelerometer is subjected to stress ...

FEM Study on Contactless Excitation of Acoustic Waves in SAWDevices

A. K. Namdeo[1], N. Ramakrishna[2], H. B. Nemade[1,2], and R. P. Palathinkal[1]

[1] Department of Electronics and Communication Engineering, Indian Institute of Technology Guwahati, Assam, India
[2] Centre for Nanotechnology. Indian Institute of Technology Guwahati, Assam, India

In this paper a finite element method(FEM) study of a surface acoustic wave (SAW)device excited by electrostatic coupling method is performed by using COMSOL Multiphysics. We have modeled a Rayleigh wave type SAW device by choosing YZ Lithium niobate as the substrate. The effect of external radio frequency (RF) field to the SAW device is analyzed. The effect of distance between the contactless ...

Modelling of SiC Chemical Vapour Infiltration Process Assisted by Microwave Heating

G. Maizza[1] and M. Longhin[1]
[1]Dipartimento di Scienza dei Materiali ed Ingegneria Chimica, Politecnico di Torino, Torino, Italy

The excessive presence of residual SiC matrix inter-fiber pores is often the main cause for the very poor mechanical strength and toughness of SiC/SiC composites manufactured by CVI (Chemical Vapour Infiltration) process. This work presents a micro/macro Microwaveassisted Chemical Vapour Infiltration (MW-CVI) model as a strategy to attack the problems above. The proposed model couples a reactor ...

High Coupling Factor Piezoelectric Materials for Bending Actuators: Analytical and Finite Elements Modeling Results

I.A. Ivan[1], M. Rakotondrabe[1], and N. Chaillet[1]
[1]FEMTO-ST Institute, University of Franche-Comte, Besançon, France

New giant piezoelectric factor materials such as PMN-PT and PZN-PT were researched during the last decade and are actually becoming commercially available. As they seem very attractive for actuator designs, we studied their potential in replacing PZT ceramics. In a first comparative approach, we tested a series of classic rectangular composite bimorph structures of different combinations of ...

Empirical Model Dedicated to the Sensitivity Study of Acoustic Hydrogen Gas Sensors Using COMSOL Multiphysics®

A. Ndieguene[1], I. Kerroum[1], F. Domingue[1], A. Reinhardt[2]
[1]Laboratoire des Microsystèmes et de Télécommunications/Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
[2]Laboratoire d’Électronique et des Technologies de l’Information, CEA, LETI Grenoble, France

Due to the increasing demand for hydrogen gas sensors for applications such as automation, transportation, or environmental monitoring, the need for sensitive and reliable sensors with a short response time is increasing. This paper presents an empirical model that studies the sensitivity of acoustic hydrogen gas sensors. A parametric study based on the variation of physical properties of ...