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.

Numerical Investigation of Electroosmotic Flow in Convergent Divergent Micronozzle

V. Gnanaraj[1], V. Mohan[1], and B. Vellaikannan[1]
[1]Thiagarajar College of Engineering, Madurai, Tamilnadu, India

A fundamental understanding of the transport phenomena in microfluidic channels is critical for systematic design and precise control of such miniaturized devices towards the integration and automation of Lab-on- a-chip devices. Electroosmotic flow is widely used to transport and mix fluids in microfluidic systems. Electroosmotic transport in convergent divergent micronozzle is significant in ...

Chemical Reaction Engineering: Difusão com Biotransformação

D. R. M. Vieira [1], S. A. Cardoso [1], A. S. Santos [1],
[1] Universidade Federal do Pará, Pará, Brasil

A biotransformação de substratos utilizando enzimas imobilizadas em nanopartículas presentes num meio fluido (substrato), contido num bioreator CSTR, foi investigada. O software COMSOL Multiphysics foi usado para simular o sistema através do uso das equações de difusão de espécies apropriadas para o consumo do substrato. Nessa investigação, a difusão na superfície da nanopartícula, onde ocorre a ...

Time-Dependent Study of Pressure Waves Generated by Square Array MEMS Ultrasound Transducers

M. A. G. Suijlen [1], R. J. Woltjer [1],
[1] Novioscan, Nijmegen, Netherlands

For non-imaging wearable ultrasound applications Novioscan is developing piezoelectric MEMS transducers. These transducers consist of a large array of micromechanical silicon membranes with piezoelectrically actuated regions to generate an out-of-plane displacement causing a pressure wave in the adjacent medium. For a typical application of echo sounding in a human body such transducers operate ...

Microfluidic Separation System for Magnetic Beads

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

It is possible to control the motion of magnetic beads using a combination of hydrodynamic and electromagnetic forces. In this work, we investigate the possibility to manipulate the motion of beads with different magnetic moments in a special microfluidic structure so as to separate them. We also experimentally prove that this structure is a suitable device to separate beads and show that the ...

Design of an Electrodynamically Actuated Microvalve Using COMSOL Multiphysics® and MATLAB®

M. Williams, J. Zito, J. Agashe, A. Sopeju, and D. Arnold
University of Florida, Gainesville, USA

This paper describes the design of a normally closed, electrodynamic microvalve.  Magnetic forces between a permanent magnet in the valve cover and a soft magnet in the valve seat hold the valve closed.  The combination of electrodynamic actuation and a mechanical restoring spring are used to open the valve.  A device model and a design optimization strategy using COMSOL ...

Designing Piezoelectric Interdigitated Microactuators using COMSOL

O. Myers [1], M. Anjanappa [2], and C. Freidhoff [3]

[1] Mississippi State University, Mississippi State, MS, USA
[2] University of Maryland Baltimore County, Baltimore, MD, USA
[3] Northrop Grumman Corporation, Electronics Systems Sector, Baltimore, MD, USA

This paper presents a methodology towards designing, analyzing and optimizing piezoelectric interdigitated microactuators using COMSOL Multiphysics. The models used in this study were based on a circularly interdigitated design that takes advantage of primarily the d33 electromechanical piezoelectric constant coefficient. Because of the symmetric nature of the devices, 2D axisymmetric models ...

Magnetic Nanoparticles for Novel Granular Spintronic Devices

A. Regtmeier[1], A. Weddemann[2], I. Ennen[3], and A. Hütten[1]
[1]Dept. of Physics, Thin Films and Physics of Nanostructures, Bielefeld University, Bielefeld, Germany
[2]Dept. of Elect. Eng. and Comp. Science, Lab. for Electromagnetic and Electronic Syst., MIT, Cambridge, MA
[3]Institute of Solid State Physics, Vienna University of Technology, Vienna, Austria

Superparamagnetic nanoparticles have a wide range of applications in modern electric devices. Recent developments have identi fied them as components for a new type of magnetoresistance sensor. We propose a model for the numeric evaluation of the sensor properties. Based on the solutions of the Landau-Lifshitz-Gilbert equation for a set of homogeneously magnetized spheres arranged in highly ...

Simulation of Deformed Solid Particles in Constrained Microfluidic Channel

M. Cartas-Ayala[1], R. Karnik[1]
[1]Massachusetts Institute of Technology, Cambridge, MA, USA

Characterization of particles has numerous applications in science and diagnostics. Recently, particle passage through constrained microchannels has been proposed to characterize particles based on their passage velocity. Nevertheless, there is no clear understanding of how the physics in this system interact. Here we quantify the effects of the flow around the particle by simulating the passage ...

Thermally Induced-Noise Reduction Using an Electrostatic Force Feedback

H. Lee, and J.V. Clark
Purdue University, West Lafayette, IN, USA

In this paper we present a method to mitigate the effect of thermally-induced noise in Micro-Electro-Mechanical Systems (MEMS) through a force feedback circuit. Inherent noise-induced vibrations, which would be inconsiderable in macro scale, are considered as a limitation in micro- and nano- scale since it diminishes the high performance of MEMS devices. For instance, depending on the stiffness ...

Air Convection on a Micro Hotplate Gas Sensor

S. Gidon[1], M. Brun[1], S. Nicoletti[1], P. Barritault[1]
[1]Commissariat Energie Atomique, LETI, Minatec Campus, Grenoble, France

Monitoring of indoor CO2 concentration is of particular interest to detect room occupancy in order to optimize power consumptions of building. One approach to monitor the indoor CO2 concentration is to use optical detection using specific absorption lines of CO2 molecules in the infrared domain close to 4.2 µm. Such optical sensors include a detector, typically a micro-bolometer, an IR source ...