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.

FE Modeling of Surfaces with Realistic 3D Roughness: Roughness Effects in Optics of Plasmonic Nanoantennas

J. Borneman[1], A. Kildishev[1], K. Chen[1], and V. Drachev[1]

[1]School of Electrical and Computer Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana, USA

COMSOL Multiphysics has been widely used to model the near and far-field electromagnetics (specifically, transmission and reflection spectra) of gold and silver nanoantenna arrays. We use a moving 3D mesh, thus preserving the DOF number and simply morphing the structure of the mesh to accommodate the moving boundary. The electromagnetics model consist of four multiphysics models, two ...

Implementation of a Paraxial Optical Propagation Method for Large Photonic Devices

J.E. Toney[1]

[1]Pennsylvania State University Electro-Optics Center, Freeport, Pennsylvania, USA

We demonstrate the use of COMSOL Multiphysics with MATLAB to model signal generation in wide-bandgap semiconductor radiation detectors. A quasi-hemispherical detector design is compared with a simple, planar detector. Results show that the quasi-hemispherical design can simply and effectively compensate for the poor hole transport of most compound semiconductor materials. In this paper we ...

Boundary conditions in multiphase, porous media, transport models of thermal processes with rapid evaporation

A. Datta[1], and A. Halder[1]
[1]Biological and Environmental Engineering, Cornell University, Ithaca, New York, USA

In modeling of thermal processing of biological materials with rapid evaporation, it is critical to provide boundary conditions consistent with the phenomena happening at the surface to accurately predict spatial temperature and moisture content for quality and safety assurance. Boundary conditions in a mathematical model are as important as governing equations itself and describe how the heat ...

Optimization of Carbon Nanotube Field Emission Arrays

B. L. Crossley[1], M. Kossler[1], P.J. Collins[1], R. A. Coutu Jr.[1], and L. A. Starman[1]

[1]Air Force Institute of Technology, Wright-Patterson AFB, Ohio, USA

Carbon nanotubes (CNTs) have been proven experimentally to be well suited for field emission applications. An optimized triode configured CNT field emission array is developed using the COMSOL Multiphysics Electrostatics Application to adjust five key physical dimensions to investigate the effects on the enhanced electric field at the CNT emitter tips. The five dimensions studied are CNT ...

Multiphysics Simulation of the Effect of Sensing and Spacer Layers on SAW Velocity

P. Zheng[1,4], D.W. Greve[2,4], and I.J. Oppenheim[3,4]

[1]Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
[2]Department of Electrical and Computer Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
[3]Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
[4]National Energy Technology Laboratory, Pittsburgh, Pennsylvania, USA

Surface acoustic wave gas sensors use a chemically sensitive resistive layer to detect gas concentration. The resistivity of the sensing material, the sensing layer thickness, and the spacer layer thickness all affect the surface wave propagation velocity. Existing analytic theory relates the change in velocity to various parameters. However some variables in this theory are not ...

Experimental Observation and Numerical Prediction of Induction Heating in a Graphite Test Article

T.A. Jankowski[1], D.P. Johnson[1], J.D. Jurney[1], J.E. Freer[1], L.M. Dougherty[1], and S.A. Stout[1]

[1]Los Alamos National Laboratory, Los Alamos, New Mexico, USA

The induction heating coils used in the plutonium casting furnaces at the Los Alamos National Laboratory are studied here. A cylindrical graphite test article has been built, instrumented with thermocouples, and heated in the induction coil that is normally used to preheat the molds during casting operations. The experiments have been modeled in COMSOL Multiphysics and the numerical and ...

Calculation of the Magnetic Field Intensity in a Rectangular Conductor Carrying Current in Electromagnetism Introductory Courses

J.C. Olivares-Galvan[1], I. Hernandez[2] , P.S. Georgilakis[3], and L.E. Campero[1]

[1]Universidad Autónoma Metropolitana, Azcapotzalco, Mexico, D.F.
[2]Centro de Investigacion y de Estudios Avanzados del IPN, Unidad Guadalajara, Guadalajara, Jalisco, Mexico
[3]School of Electrical and Computer Engineering, National Technical University of Athens, Athens, Greece

This paper describes a type of didactic material used when teaching electromagnetism. The purpose is to guide the students to verify the results of a Finite Element (FE) simulation using those obtained analytically. This procedure has shown to be of great help during their learning of the FE method. The example in this paper uses a 2D analytical method to estimate the magnetic field generated by ...

Study of Fluid and Mass Adsorption Model in the QCM-D Sensor for Characterization of Biomolecular Interaction

H.J. Kwon[1], C.K. Bradfield[1], B.T. Dodge[1], and G.S. Agoki[1]
[1]Department of Engineering and Computer Science, Andrews University, Berrien Springs, Michigan, USA

Increasing attention has been paid to application of the quartz crystal microbalance with dissipation (QCM-D) sensor for monitoring biomolecular interactions. This paper focuses on a practical application of protein-protein binding affinity measurement at low concentrations and minimal sample sizes (50-200 μl of 20-200 nM), which results in low signal measurement. A model simulating fluid ...

Image-based Simulation of Electrical Impedance Techniques Applied on the Human Thorax for Cardio-pulmonary Applications

A. Harkara[1], R.M. Heethaar[2], R.T. Cotton[1], and F.K. Hermans[2]

[1]Simpleware Ltd., Exeter, UK
[2]VU University Medical Center, Amsterdam, Netherlands

For medical diagnostic purposes there is an increasing need for non-(or minimal) invasive techniques to measure all kinds of parameters that can provide insight in the functioning of cells, organs or organ systems. Currently, Impedance Cardiography (ICG) is used for measurements of the heart and Electric Impedance Tomography (EIT) is used for investigating lung tissue condition. The PDE is ...

Modeling Hydrogen Permeation through a Thin TiO2 Film Deposited on Pd

Z. Qin[1], Y. Zeng[1], and D.W. Shoesmith[1]

[1]The University of Western Ontario, London, Ontario, Canada

Models that describe hydrogen permeation through a thin TiO2 film deposited on Pd have been developed based on a mass-balance equation consisting of diffusion, reversible hydrogen absorption/desorption, and irreversible hydrogen trapping. These models are solved by the finite element method using COMSOL Multiphysics. By comparing model simulations with experimental permeation curves, values of ...