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.

Near-Wall Dynamics of Microbubbles in an Acoustical Trap - new

L. Wright[1], G. Memoli[1], P. Jones[2], E. Stride[3]
[1]National Physical Laboratory, Teddington, UK
[2]University College London, London, UK
[3]University of Oxford, Oxford, UK

Understanding the interactions between microbubbles and surfaces is key to the successful deployment of microbubbles in a range of applications. Two important examples are their use as a drug delivery mechanism, and their potential use of acoustically-driven bubbles as microscale sensors. Drug delivery with bubbles involves sonication at high frequency close to a boundary, and sensing with ...

Computational Simulation of Electrohydrodynamic Systems Pertaining to Micro and Nano scale Fluid Flow Phenomenon

M. Seiler[1], and B. Kirby[2]
[1]Department of Engineering Physics, Cornell
University, NY, USA
[2]Department of Mechanical Engineering, Cornell
University, NY, USA

Modeling of 3D AC electro-osmotic pumps is relevant to the creation of portable or implantable lab-on-a-chip devices for mm/s tunable fluid flows attainable with battery scale voltages. In this analysis using COMSOL Multiphysics we investigate the modeling challenges of computationally calculating systems of fluid flow phenomena governed by AC Electroosmosis in the micro and nano scale regimes.

Surface Acoustic Wave Properties (SAW) and Acoustic Streaming Characterization for Annular and Curved Electrodes on 128˚ Y-Cut, X-Propagating LiNbO3

G. Potter[1], N. Tokranova[1], S. Gattu[1], J. Castracane[1]
[1]SUNY College of Nanoscale Science and Engineering, Albany, NY, USA

Microfluidic devices and lab-on-a-chip (LOC) require the ability to transport or pump reagents or reaction products, the ability to effectively mix small volumes of fluid, and provide direct data display. Surface acoustic wave (SAW) driven acoustic streaming generated by a piezoelectric material represents a developing solution to many of the demands of these devices with advantages over other ...

A Study of Lubricating Flows in MEMS Bearings

E. Gutierrez-Miravete[1], and J. Streeter[2]

[1]Department of Engineering and Science, Rensselaer at Hartford, Hartford, Connecticut, USA
[2]Optiwind, Torrington, Connecticut, USA

The bearing and shaft are part of a safe and arm device constructed as an assembly by a multi-layer additive/subtractive plating and planarization processes (EFAB technology). Devices are constructed by a multi-layer additive/subtractive planarization process. This paper evaluates the lubricating flow between the shaft and journal of the MEMS bearing for seven configurations. The pressure ...

Numerical Study of Exciton States of Core?shell CdTe/CdS Nanotetrapods by using COMSOL Multiphysics

Y. Yao?and K. Sakoda
National Institute for Materials Science
University of Tsukuba
Japan

This paper showed: * The electronic states of core-shell tetrapod with various shell thickness were calculated. Lowest 20 electron and hole wave functions have A1 or T2 symmetry. * At t=1.2 nm, the carriers separation is not serious, core-shell tetrapod is not apparent type II heterostructure. * Exciton states were investigated as a function of t. For large t, the lowest exciton state has T2 ...

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 ...

Multiphysics System Simulation for MEMS Inertial Sensors

R. Sattler
University of Applied Sciences, Regensburg, Germany

This paper gives an overview of modelling microsensors on geometry and system level. The focus will be on the generation of the multiphysics reduced order system model and the coupling with package and ASIC models. The method is based on modal superposition. This means all the details of the sensor can be considered in a finite element model. The mechanical mode shapes of this model form the ...

Motion of Uncharged Particles in Electroosmotic Flow through a Wavy Cylindrical Channel

N. Qudus[1], T. Mahbub[1], S. A. Ali[1], and M. Shajahan[1]
[1] Bangladesh University of Engineering and Technology, Dhaka Bangladesh

A finite element model is employed to describe the electric potential distribution and electroosmotic flow field inside a wavy cylindrical channel. The model uses coupled Laplace and Poisson-Boltzmann to evaluate the electric potential distribution inside the channel. It also contains continuity and Navier–Stokes equations for the solution of fluid flow. A particle trajectory model was ...

AC Electrothermal Characterization of Doped-Si Heated Microcantilevers Using Frequency-Domain Finite Element Analysis - new

K. Park[1], S. Hamian[1], A. M. Gauffreau[2], T. Walsh[2]
[1]Mechanical Engineering Department, University of Utah, Salt Lake City, UT, USA
[2]Department of Mechanical, Industrial & Systems Engineering, University of Rhode Island, Kingston, RI, USA

This work investigates the frequency-dependent electrothermal behaviors of freestanding doped-silicon heated microcantilever probes operating under the periodic (ac) Joule heating. The transient heat conduction equation for each component (i.e., the low-doped heater region, the high-doped constriction region, and the high-doped leg region) is solved using the general heat transfer module for DC ...

Simulations of Micropumps Based on Tilted Flexible Structures - new

M. J. Hancock[1], N. H. Elabbasi[1], M. C. Demirel[2]
[1]Veryst Engineering, LLC., Needham, MA, USA
[2]Pennsylvania State University, University Park, PA, USA

Pumping liquids at small scales is challenging because of the principle of reversibility: in a viscous regime, the flow streamlines through a fixed geometry are the same regardless of flow direction. Recently we developed a class of microfluidic pump designs based on tilted flexible structures that combines the concepts of cilia (flexible elastic elements) and rectifiers (e.g., Tesla pump). We ...