Senior Materials Scientist, NASA Marshall Space Flight Center
A scientific hypothesis states that cryogenic trapped water is just under the surface of lunar soil at the poles in permanently shadowed craters. Microwave energy can be used to efficiently extract this water from permafrost. COMSOL permits calculation of the heating of simulated lunar soil using measured temperature dependent dielectric properties. Calculations at different microwave ...
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 ...
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. ...
M.G. Levy, X. Liang, R.M. Stratt, and P.M. Weber
Department of Chemistry, Brown University, Providence, Rhode Island, USA
Identifying molecules requires associating molecular structures with their electronic energy levels. In this paper we introduce a novel technique for the calculation of molecular Rydberg levels. The technique allows for easy visualization of the associated wavefuntions to make unambiguous assignments. The value calculated for the 3p state of trimethylamine is most closely in agreement with ...
K. Song, and H. Knickle
Department of Chemical Engineering, University of Rhode Island, Kingston Rhode Island, USA
In this paper we present a study of the time dependent analysis of a metal hydride bed (MHB) which provides constant flow to a fuel cell at required power loading and pressure. The hydrogen gas phase pressure, the hydrogen concentration in the metal hydride and the hydrogen desorption rate are consider as key variables in this study. Both the space scale and time scale analysis are performed. ...
P. Masson, and R. Meinke
Advanced Magnet Lab, Palm Bay, Florida, USA
Superconductors have the unique capability of trapping magnetic flux. This feature has the potential to enable and improve several applications including high power density rotating machines. Current material used as trapped flux magnets (TFM) is single domain YBCO that present numerous limitations interms of performance, stability and size. One way to overcome the limitations is to use thin ...
M. V. Kisin, R. G. W. Brown, and H. S. El-Ghoroury
Ostendo Technologies, Inc., Carlsbad, CA, USA
We present a modeling software package developed at Ostendo Technologies for analysis and design of semiconductor laser and light-emitting diodes. The current database of material parameters supports complete group of III-Nitride alloys used in visible spectrum applications and can be readily extended to all III-V compounds. Self-consistent multi-band quantum-mechanical model for carrier energy ...
Department of Mechanical Engineering, College of Engineering and Petroleum, Kuwait University, Safat, Kuwait
In this study, numerical simulations of mixing in turbulent flow, subject to a change in density, are performed. Attention is focused on the binary mixing between two streams of fluid in which a variable density step are formed due to a difference in the temperature. This binary mixing problem performed by assuming low Mach number flow. The results demonstrate the variable density effects and ...
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 ...
W. Clark, and M. Lindblad
Chemical Engineering Department, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
Two-phase electrophoresis is a separation method that combines aqueous two-phase partitioning with electrophoresis and has promise for large scale recovery of biological products. Aqueous two-phase systems formed by adding two polymers, like dextran and polyethylene glycol, to water provide some separation of dissolved species due to differences in solubility of solutes between the phases. ...