Design and Nuclear-Safety Related Simulations of Bare-Pellet Test Irradiations for the Production of Pu-238 in the High Flux Isotope Reactor Using COMSOL
J.D. Freels, P.K. Jain, R.W. Hobbs
Oak Ridge National Laboratory, Oak Ridge, TN, USA
The Oak Ridge National Laboratory (ORNL) is developing technology to re-establish the capability to produce plutonium-238 for the National Aeronautics and Space Administration (NASA) as a power source material for powering vehicles while in deep-space. The High Flux Isotope Reactor (HFIR) of ORNL has been utilized to perform test irradiations of in-capsulated neptunium oxide (NpO2) and aluminum ...
J.E. Rayas-Sánchez, J. Aguilar-Torrentera, Z. Brito-Brito, J.C. Cervantes-González, C.A. López
Universidad Jesuita de Guadalajara, Tlaquepaque, Jalisco, Mexico
Intel Guadalajara Design Center, Tlaquepaque, Jalisco, Mexico
We perform EM simulations of a low-pass microstrip filter consisting of a cross-junction open stub and two unit sections implemented as defected ground structures (DGS). The defect introduced by unit sections corresponds to an etched lattice on the copper backside ground plane. The filter presents wide and deep attenuation characteristics in the stopband. Different model implementations were ...
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 ...
Analysis of Superheater Tubes with Mutual Irradiation as Applied to a Solar Receiver Steam Generator
N. Lemcoff, S. Wyatt
Rensselaer Polytechnic Institute, Hartford, CT, USA
Alstom Power, Windsor, CT, USA
The objective of this paper is to analyze the temperature variations within a superheater tube of a solar receiver steam generator. The tube is heated by concentrated, collimated solar irradiation with major cooling by an internal steam flow. The influence of heat loss by radiation, internal convection, and conduction are considered. Analytical models are obtained for an isolated tube, and the ...
A Study of the Effects of Mounting Supports, and Dissipation on a Piezoelectric Quartz Double-Ended Tuning Fork Gyroscope
G. Choi, Y. Yong
Rutgers University, New Brunswick, NJ, USA
A COMSOL model of a piezoelectric quartz double ended tuning fork gyroscope was implemented. The gyroscope has two detection modes; the first mode detects the angular velocity about a z-axis perpendicular to the tuning fork plane (x-y plane), while the second mode detects the angular velocity about a y-axis that is the longitudinal axis along the length of the tuning fork. Eigenfrequency ...
R. Nopper, J. Clark, C. Miller
DuPont Company, Wilmington, DE, USA
DuPont Company, Beaumont, TX, USA
Stress and failure in the earth have long been observed to couple to hydrogeology. Poroelastic models, introduced by soil scientists, can account for strong two-way coupling between porous crustal rock formations and their pore fluids. Current efforts to provide new energy resources (water injection in EGS, enhanced oil recovery) and to reduce pollution (CO2 sequestration, deepwell disposal) ...
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 ...
M. Liu, G. Zhao
University of Regina, Regina, SK, Canada
This study presents a oil-gas two-phase linear flow EMH model using COMSOL Multiphysics simulator. Special attention is focused on reservoirs with characteristics for which steam injection is not attractive or feasible such as low permeability, thin-zone, and extra-heavy oil reservoirs. Comparisons showed that cumulative oil production obtained by EM heating is better than what is achieved by a ...
The Dow Chemical Company, Midland, MI, USA
Photovoltaic systems can degrade with moisture. The addition of an edge-seal containing a desiccant can reduce the amount of water reaching the interior. This report discusses the modeling of the water transport into the system to determine the amount of edge seal and desiccant required. The moving freezing front of the Stefan heat-transport problem is used to model a moving moisture ...
L. Graber, N.G. Suttell, D. Shah, D.G. Crook, C.H. Kim, J. Ordonez, S. Pamidi
Center for Advanced Power Systems, Florida State University, Tallahassee, FL, USA
Heat sinks for cryogenic applications using helium gas as the coolant are not readily available. They require to be designed specifically for the intended application. A finite element model was developed to study the feasibility and optimize the design. The FEM computing package COMSOL Multiphysics allowed to couple fluid flow and heat transfer as needed. An experiment was designed to validate ...