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 abrangem 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.

Orientation of Piezoelectric Crystals and Acoustic Wave Propagation

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

Surface acoustic wave (SAW) devices are commonly used as wireless filters, resonators, and sensors. The confinement of acoustic energy near the surface of a piezoelectric substrate in a SAW sensor makes it highly sensitive for discerning surface perturbation. As sensors, SAW devices have the potential to provide a high-performance sensing platform with capabilities of remote and high-temperature ...

Numerical Simulation of Phonon Dispersion Relations for Phononic Crystals

G. Zhu[1], E.M. Dede[1]
[1]Toyota Research Institute of North America, Ann Arbor, MI, USA

In previous work, a two-dimensional (2D) model was carried out to simulate the phononic band structure of a phononic crystal with square lattice structure, but this model did not account for the out-of-plane phonon dispersions [1]. In fact, for 2D films used for coating materials, it is more interesting to understand their cross-plane properties. In this work, the phonon dispersion relation of ...

Modeling of Chloride Transport in Cracked Concrete: a 3-D Image–Based Microstructure Simulation

Y. Lu[1], E. Garboczi[1], D. Bentz[1]
[1]National Institute of Standards and Technology, Gaithersburg, MD, USA

The prediction of concrete materials service life is not easy, because the complex heterogeneous microstructure and the random nature of concrete materials. Study the presence of cracks in concrete and their effect on coupled reaction and transport are of great interest in civil engineering. Cracks with different widths and depths will reduce the cover thickness and accelerate the migration of ...

Optimization of Artificial Diffusion Stabilization Techniques and Corresponding Mesh Density Distribution in Drift Dominated Transport of Diluted Species

J. Jadidian[1], M. Zahn[1], N. Lavesson[2], O. Widlund[2], K. Borg[2]
[1]Massachusetts Institute of Technology, Cambridge, MA, USA
[2]ABB Corporate Research, Västerås, Sweden

This paper presents an optimized combination of artificial diffusion techniques to stabilize a drift dominated streamer discharge model which includes COMSOL Multiphysics’ Transport of Diluted Species modules for positive ion, negative ion, and electron charge densities, coupled through the Electrostatic module. A Thermal Conduction and Convection module is responsible for the heat transfer in ...

Modeling Internal Heating of Optoelectronic Devices Using COMSOL

N. Brunner[1][,][2]
[1]Voxtel, Inc, Beaverton, OR, USA
[2]University of Oregon, Eugene, OR, USA

In this paper the heat transfer module in COMSOL is utilized to simulate internal heating of an Avalanche Photodiode due to light-induced current through a resistivity that depends on charge carrier concentrations in the device. Initial tests are done by modeling the heating process on a previously-solved silicon p-n junction as a proof of concept before advancing to a more complicated geometry. ...

Modeling of DC Discharges in Argon at Low Pressures

V. Gorokhovsky[1]
[1]Vapor Technologies, Inc., Longmont, CO, USA

The glow discharges in argon at pressures of 1 to 20 mTorr are modeling using COMSOL Plasma Module. DC glow discharge with secondary electron emission is compared to low pressure arc with thermionic emission. Boundary conditions on dielectric discharge tube walls are compared to that of metallic discharge tube walls. Modeling revealed that electron emission mechanisms as well as boundary ...

Irrotational Motion of an Incompressible Fluid Past a Wing Section in an Unbounded Region

J. Russell[1]
[1]Florida Institute of Technology, Melbourne, FL, USA

Developers of numerical models who address the title problem face several hurdles, such as: (1), the need to formulate boundary conditions applicable in an unbounded region; (2), The need to specify conditions suitable to ensure a unique solution in a doubly connected region; and (3), The need to allow the interior boundary to have a sharp edge, such as a cusp. The aim of the work reported ...

Modeling and Prediction of Line Pattern Collapse

D. Bassett[1], M. Carcasi[1], W. Printz[1]
[1]Tokyo Electron America, Austin, TX, USA

In semiconductor manufacturing, effective cleaning of structures with liquid is one of the most important and potentially difficult process steps. It is important because it remains the cheapest and most cost-effective method to remove particles and residues from the structures in order to prevent defects, but can also be difficult because as the structures dry, surface tension forces can cause ...

Modeling Void Drainage with Thin Film Dynamics

J.J. Gangloff Jr.[1], W.R. Hwang[2], S.G. Advani[1]
[1]Center for Composite Materials, Department of Mechanical Engineering, University of Delaware, Newark, DE, USA
[2]School of Mechanical Engineering, Gyeongsang National University, Jinju, Gyeongsangnam-do, Korea

Voids in composite materials can lead to degraded structural performance. The following is a study of voids or bubbles in uncured viscous polymer resin during composites processing. The goal is to determine if voids can successfully migrate towards vacuum pathways, coalesce with the pathways, and escape. Inherent to the coalescence process is the drainage and rupture of the resin thin film ...

Finite Element Solution of Nonlinear Transient Rock Damage with Application in Geomechanics of Oil and Gas Reservoirs

S. Enayatpour[1], T. Patzek[1]
[1]The University of Texas at Austin, Austin, TX, USA

The increasing energy demand calls for advances in technology which translate into more accurate and complex simulations of physical problems. Understanding the rock damage is essential to understanding the geomechanics of hydrocarbon reservoirs. The fragile microstructure of some rocks makes it difficult to predict the propagation of fracture in these rocks, therefore a mathematical model is ...