B. L. Crossley, M. Kossler, P.J. Collins, R. A. Coutu Jr., and L. A. Starman
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 ...
An Analysis of Heat Conduction with Change of Phase with Application to the Solidification of Copper
J. Michalski, and E. Gutirrez-Miravete
Rensselaer at Hartford, Hartford, Connecticut, US
The goal of this study was to determine the possibility of using the finite element in COMSOL Multiphysics program to obtain a high accuracy solution to a moving boundary problem, specifically, the solidification of copper. A one-dimensional geometry in Cartesian coordinates was used to investigate the solidification of initially liquid copper from a chilled wall maintained at fixed temperature. ...
T.A. Jankowski, D.P. Johnson, J.D. Jurney, J.E. Freer, L.M. Dougherty, and S.A. Stout
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, I. Hernandez , P.S. Georgilakis, and L.E. Campero
Universidad Autónoma Metropolitana, Azcapotzalco, Mexico, D.F.
Centro de Investigacion y de Estudios Avanzados del IPN, Unidad Guadalajara, Guadalajara, Jalisco, Mexico
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 ...
FE Modeling of Surfaces with Realistic 3D Roughness: Roughness Effects in Optics of Plasmonic Nanoantennas
J. Borneman, A. Kildishev, K. Chen, and V. Drachev
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 ...
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 ...
Study of Fluid and Mass Adsorption Model in the QCM-D Sensor for Characterization of Biomolecular Interaction
H.J. Kwon, C.K. Bradfield, B.T. Dodge, and G.S. Agoki
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 ...
Z. Qin, Y. Zeng, and D.W. Shoesmith
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 ...
A.E. Varela, and J.C. García
University of Carabobo, Valencia, Venezuela
Most reactor designs are based on pseudo homogeneous models. This paper studies the COMSOL simulation of a packed bed reactor using a 2-D heterogeneous model. The case considered was a packed reactor with spherical catalyst for oxidation of o-xylene in air to phthalic anhydride. Large differences in intra-pellet temperature were found in comparison with the average temperatures resulting from ...
Boundary conditions in multiphase, porous media, transport models of thermal processes with rapid evaporation
A. Datta, and A. Halder
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 ...