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Fundamentals of Melt-Water Interfacial Transport Phenomena: Improved Understanding for Innovative Safety Technologies in ALWRs (open access)

Fundamentals of Melt-Water Interfacial Transport Phenomena: Improved Understanding for Innovative Safety Technologies in ALWRs

The interaction and mixing of high-temperature melt and water is the important technical issue in the safety assessment of water-cooled reactors to achieve ultimate core coolability. For specific advanced light water reactor (ALWR) designs, deliberate mixing of the core-melt and water is being considered as a mitigative measure, to assure ex-vessel core coolability. The goal of this work is to provide the fundamental understanding needed for melt-water interfacial transport phenomena, thus enabling the development of innovative safety technologies for advanced LWRs that will assure ex-vessel core coolability. The work considers the ex-vessel coolability phenomena in two stages. The first stage is the melt quenching process and is being addressed by Argonne National Lab and University of Wisconsin in modified test facilities. Given a quenched melt in the form of solidified debris, the second stage is to characterize the long-term debris cooling process and is being addressed by Korean Maritime University in via test and analyses. We then address the appropriate scaling and design methodologies for reactor applications.
Date: April 26, 2005
Creator: Anderson, M.; Corradini, M.; Bank, K.Y.; Bonazza, R. & Cho, D.
Object Type: Report
System: The UNT Digital Library
Overview of energy storage applications (open access)

Overview of energy storage applications

Sandia National Laboratories has been studying Energy Storage Systems since the late 1970s. Sandia started by applying their defense program battery experience to larger stationary systems, eventually joining in the formation of the Utility Battery Group which has since evolved into the Energy Storage Association. Sandia's role, as a Department of Energy funded program is to look ahead at emerging technologies, perform early R and D and identify applications for Energy Storage Systems that offer significant benefit to the nation's electricity providers and users. In order to identify applications of energy storage, a two-phase Opportunities Analysis was conceptualized in FY94. Phase 1 of the project was completed and published in 1995 (SAND94-2605). Phase 2 of the project is an extension of Phase 1 to reexamine the identified applications in the dynamic environment of today. In a preliminary assessment of national benefits, SNL estimated that generation and transmission applications of storage could represent $17.2B in national benefits. In Phase 1 of the Opportunities Analysis, the T and D benefits were found to be significantly higher than previous estimates Phase 2 of the study, which began in late 1998, includes a refinement of the technical and economic understanding of the role of …
Date: April 26, 2000
Creator: BOYES,JOHN D.
Object Type: Article
System: The UNT Digital Library
Technologies for energy storage flywheels and super conducting magnetic energy storage (open access)

Technologies for energy storage flywheels and super conducting magnetic energy storage

A flywheel is an electromechanical storage system in which energy is stored in the kinetic energy of a rotating mass. Flywheel systems under development include those with steel flywheel rotors and resin/glass or resin/carbon-fiber composite rotors. The mechanics of energy storage in a flywheel system are common to both steel- and composite-rotor flywheels. In both systems, the momentum of the rotating rotor stores energy. The rotor contains a motor/generator that converts energy between electrical and mechanical forms. In both types of systems, the rotor operates in a vacuum and spins on bearings to reduce friction and increase efficiency. Steel-rotor systems rely mostly on the mass of the rotor to store energy while composite flywheels rely mostly on speed. During charging, an electric current flows through the motor increasing the speed of the flywheel. During discharge, the generator produces current flow out of the system slowing the wheel down. The basic characteristics of a Flywheel system are shown. Steel flywheel systems are currently being marketed in the US and Germany and can be connected in parallel to provide greater power if required. Sizes range from 40kW to 1.6MW for times of 5--120 seconds. At this time sales are limited but growing. …
Date: April 26, 2000
Creator: BOYES,JOHN D.
Object Type: Article
System: The UNT Digital Library
Microstructure Development in Nickel Base Superalloys during Weld Thermal Cycle (open access)

Microstructure Development in Nickel Base Superalloys during Weld Thermal Cycle

Welding plays an important role in the economical reuse and reclamation of used and failed nickel base superalloy blades. Previous research on microstructure development during laser beam welding of a single crystal CMSX4 alloy [Ref. l] showed non-equilibrium y/y{prime} microstructure development. In addition, the y{prime} precipitates were found to be irregular in shape and atom probe field ion microscopy illustrated the presence of diffusional concentration profile within the y phase in the as welded condition. To understand the above microstructure characteristics, y{prime} precipitation from y phase was investigated during continuous cooling from solutionizing temperature.
Date: April 26, 2000
Creator: Babu, S. S. & David, S. A.
Object Type: Article
System: The UNT Digital Library
Biogeophysical effects of CO2-fertilization on global climate (open access)

Biogeophysical effects of CO2-fertilization on global climate

CO{sub 2}-fertilization affects plant growth, which modifies surface physical properties, altering the surface albedo, and fluxes of sensible and latent heat. We investigate how such CO{sub 2}-fertilization effects on vegetation and surface properties would affect the climate system. Using a global three-dimensional climate-carbon model that simulates vegetation dynamics, we compare two multi-century simulations: a ''Control'' simulation with no emissions, and a ''Physiol-noGHG'' simulation where physiological changes occur as a result of prescribed CO{sub 2} emissions, but where CO{sub 2}-induced greenhouse warming is not included. In our simulations, CO{sub 2}-fertilization produces warming; we obtain an annual- and global-mean warming of about 0.65 K (and land-only warming of 1.4 K) after 430 years. This century-scale warming is mostly due to a decreased surface albedo associated with the expansion of the Northern Hemisphere boreal forests. On decadal time scales, the CO{sub 2} uptake by afforestation should produce a cooling effect that exceeds this albedo-based warming; but if the forests remain in place, the CO{sub 2}-enhanced-greenhouse effect would diminish as the ocean equilibrates with the atmosphere, whereas the albedo effect would persist. Thus, on century time scales, there is the prospect for net warming from CO{sub 2}-fertilization of the land biosphere. Further study is …
Date: April 26, 2006
Creator: Bala, G.; Caldeira, K.; Mirin, A.; Wickett, M.; Delire, C. & Phillips, T. J.
Object Type: Article
System: The UNT Digital Library
Exotic Mesons, Theory and Experiment (open access)

Exotic Mesons, Theory and Experiment

In this talk I summarize the status of exotic mesons, including both theoretical expectations and experimental candidates. The current experimental candidates are ''spin-parity exotics'', since these are most often considered possible hybrid mesons, the theoretical discussion will be mainly concerned with hybrids. The exotic meson candidates discussed are the surprisingly light {pi}{sub 1} (1400) and {pi}{sub 1} (1600).
Date: April 26, 2001
Creator: Barnes, T.
Object Type: Article
System: The UNT Digital Library
Hybrid Baryons, A Brief Review (open access)

Hybrid Baryons, A Brief Review

This contribution is a brief review of the status of hybrid baryons, which are hypothetical baryons that incorporate a gluonic excitation. We first summarize the status of hybrid mesons, since this closely related topic has seen considerable recent activity with the identification of two exotic candidates. Next we review theoretical expectations for the masses and quantum numbers of hybrid baryons, which have come from studies of the bag model, QCD sum rules and the flux tube model. Finally hybrid baryon experiment is discussed, including suggestions for experimenters at COSY.
Date: April 26, 2001
Creator: Barnes, T.
Object Type: Article
System: The UNT Digital Library
MESON2000 Conference Summary (open access)

MESON2000 Conference Summary

This short contribution is a lite MESON2000 conference summary. As appropriate for the 600th anniversary of the Jagellonian University, it begins with a brief summary of the last 600 years of European history and its place in hadron physics. Next a ''physicist chirality'' order parameter PC is introduced. When applied to MESON2000 plenary speakers this order parameter illustrates the separation of hadron physicists into disjoint communities. The individual plenary talks in MESON2000 are next sorted according to the subconference associated with each of the 36 plenary speakers. Finally, I conclude with a previously unreported Feynman story regarding the use of models in hadron physics.
Date: April 26, 2001
Creator: Barnes, T.
Object Type: Article
System: The UNT Digital Library
Synthesis and optimization of integrated chemical processes (open access)

Synthesis and optimization of integrated chemical processes

This is the final technical report for the project titled ''Synthesis and optimization of integrated chemical processes''. Progress is reported on novel algorithms for the computation of all heteroazeotropic compositions present in complex liquid mixtures; the design of novel flexible azeotropic separation processes using middle vessel batch distillation columns; and theory and algorithms for sensitivity analysis and numerical optimization of hybrid discrete/continuous dynamic systems.
Date: April 26, 2002
Creator: Barton, Paul I. & Evans, Lawrence B.
Object Type: Report
System: The UNT Digital Library
Mission Need Statement: Calcine Disposition Project Major Systems Acquisition Project (open access)

Mission Need Statement: Calcine Disposition Project Major Systems Acquisition Project

This document identifies the need to establish the Calcine Disposition Project to determine and implement the final disposition of calcine including characterization, retrieval, treatment (if necessary), packaging, loading, onsite interim storage pending shipment to a repository or interim storage facility, and disposition of related facilities.
Date: April 26, 2007
Creator: Beck, J. T.
Object Type: Report
System: The UNT Digital Library
Stochastic algorithms for the analysis of numerical flame simulations (open access)

Stochastic algorithms for the analysis of numerical flame simulations

Recent progress in simulation methodologies and high-performance parallel computers have made it is possible to perform detailed simulations of multidimensional reacting flow phenomena using comprehensive kinetics mechanisms. As simulations become larger and more complex, it becomes increasingly difficult to extract useful information from the numerical solution, particularly regarding the interactions of the chemical reaction and diffusion processes. In this paper we present a new diagnostic tool for analysis of numerical simulations of reacting flow. Our approach is based on recasting an Eulerian flow solution in a Lagrangian frame. Unlike a conventional Lagrangian view point that follows the evolution of a volume of the fluid, we instead follow specific chemical elements, e.g., carbon, nitrogen, etc., as they move through the system . From this perspective an ''atom'' is part of some molecule of a species that is transported through the domain by advection and diffusion. Reactions cause the atom to shift from one chemical host species to another and the subsequent transport of the atom is given by the movement of the new species. We represent these processes using a stochastic particle formulation that treats advection deterministically and models diffusion and chemistry as stochastic processes. In this paper, we discuss the …
Date: April 26, 2004
Creator: Bell, John B.; Day, Marcus S.; Grcar, Joseph F. & Lijewski, Michael J.
Object Type: Article
System: The UNT Digital Library
Energy Efficiency in Heavy Vehicle Tires, Drivetrains, and Braking Systems (open access)

Energy Efficiency in Heavy Vehicle Tires, Drivetrains, and Braking Systems

This document was prepared to support the primary goals of the Department of Energy, Office of Heavy Vehicle Technologies. These were recently stated as follows: ''Develop by 2004 the enabling technologies for a class 7-8 truck with a fuel efficiency of 10 mpg (at 65 mph) which will meet prevailing emission standards. For Class 3-6 trucks operating on an urban driving cycle, develop by 2004 commercially viable vehicles that achieve at least double the fuel economy of comparable current vehicles (1999), and as a research goal, reduce criteria pollutants to 30% below EPA standards. Develop by 2004 the diesel engine enabling technologies to support large-scale industry dieselization of Class 1 and 2 trucks, achieving a 35 % fuel efficiency improvement over comparable gasoline-fueled trucks, while meeting applicable emissions standards.'' The enabling technologies for improving the fuel efficiency of trucks, include not only engine technologies but also technologies involved with lowering the rolling resistance of tires, reducing vehicle aerodynamic drag, improving thermal management, and reducing parasitic frictional losses in drive train components. Opportunities also exist for making better use of the energy that might ordinarily be dissipated during vehicle braking. Braking systems must be included in this evaluation since safety in …
Date: April 26, 2000
Creator: Blau, Peter J.
Object Type: Report
System: The UNT Digital Library
PILOT TESTING OF MERCURY OXIDATION CATALYSTS FOR UPSTREAM OF WET FGD SYSTEMS (open access)

PILOT TESTING OF MERCURY OXIDATION CATALYSTS FOR UPSTREAM OF WET FGD SYSTEMS

This document summarizes progress on Cooperative Agreement DE-FC26-01NT41185, Pilot Testing of Mercury Oxidation Catalysts for Upstream of Wet FGD Systems, during the time period January 1, 2002 through March 31, 2002. The objective of this project is to demonstrate at pilot scale the use of solid honeycomb catalysts to promote the oxidation of elemental mercury in the flue gas from coal combustion. The project is being funded by the U.S. DOE National Energy Technology Laboratory under Cooperative Agreement DE-FC26-01NT41185. EPRI, Great River Energy (GRE) and City Public Service (CPS) of San Antonio are project co-funders. URS Group is the prime contractor. The mercury catalytic oxidation process under development uses catalyst materials applied to honeycomb substrates to promote the oxidation of elemental mercury in the flue gas from coal-fired power plants that have wet lime or limestone flue gas desulfurization (FGD) systems. Oxidized mercury is removed in the wet FGD absorbers and co-precipitates in a stable form with the byproducts from the FGD system. The co-precipitated mercury does not appear to adversely affect the disposal or reuse properties of the FGD byproduct. The current project will test previously identified, effective catalyst materials at a larger, pilot scale and in a commercial …
Date: April 26, 2002
Creator: Blythe, Gary M.
Object Type: Report
System: The UNT Digital Library
Making european-style community wind power development work in theUnited States (open access)

Making european-style community wind power development work in theUnited States

Once primarily a European phenomenon, community wind power development--defined here as one or more locally owned, utility-scale wind turbines interconnected on either the customer or utility side of the meter--is gaining a foothold in an increasing number of states throughout the United States. This article describes the various policies and incentives that Minnesota, Wisconsin, Iowa, and Massachusetts are using to support community wind power development, and how state and federal support influences the types of projects and ownership structures that are being developed. Experience in these states demonstrates that, with an array of incentives and creative financing schemes targeted at community-scale projects, there are opportunities to make community wind work in the United States.
Date: April 26, 2004
Creator: Bolinger, Mark A.
Object Type: Article
System: The UNT Digital Library
System Administration Guide for FEMIS Version 1.5 (open access)

System Administration Guide for FEMIS Version 1.5

The Federal Emergency Management System (FEMIS) is an emergency management planning and response tool. The FEMIS System Administration Guide provides information on FEMIS System Administrator activities as well as the utilities that are included with FEMIS.
Date: April 26, 2002
Creator: Bower, John C.; Burnett, Robert A.; Carter, Richard J.; Downing, Timothy R.; Homer, Brian J.; Holter, Nancy A. et al.
Object Type: Text
System: The UNT Digital Library
Newton Descent Observer for Nonlinear Discrete-Time Systems (open access)

Newton Descent Observer for Nonlinear Discrete-Time Systems

None
Date: April 26, 2005
Creator: Boyle, J & Wen, J
Object Type: Article
System: The UNT Digital Library
What's New on the Web? Clean Cities Alternative Fuel Information Series Fact Sheet (open access)

What's New on the Web? Clean Cities Alternative Fuel Information Series Fact Sheet

This fact sheet describes what was newly added to the AFDC and Clean Cities (and other DOE) Web sites.
Date: April 26, 2001
Creator: Brodt-Giles, D.
Object Type: Book
System: The UNT Digital Library
Gas Generation from K East Basin Sludges - Series II Testing (open access)

Gas Generation from K East Basin Sludges - Series II Testing

This report describes work to examine the gas generation behavior of actual K East (KE) Basin floor, pit and canister sludge. Mixed and unmixed and fractionated KE canister sludge were tested, along with floor and pit sludges from areas in the KE Basin not previously sampled. The first report in this series focuses on gas generation from KE floor and canister sludge collected using a consolidated sampling technique. The third report presents results of gas generation testing of irradiated uranium fuel fragments with and without sludge addition. The path forward for management of the K Basin Sludge is to retrieve, ship, and store the sludge at T Plant until final processing at some future date. Gas generation will impact the designs and costs of systems associated with retrieval, transportation and storage of sludge. This report was originally published in March 2001. In January 2004, a transcription error was discovered in the value reported for the uranium metal content of KE North Loadout Pit sample FE-3. This revision of the report corrects the U metal content of FE-3 from 0.0013 wt% to 0.013 wt%.
Date: April 26, 2004
Creator: Bryan, Samuel A.; Delegard, Calvin H.; Schmidt, Andrew J.; Sell, Rachel L.; Silvers, Kurt L.; Gano, Susan R. et al.
Object Type: Report
System: The UNT Digital Library
Cobra-IE Evaluation by Simulation of the NUPEC BWR Full-Size Fine-Mesh Bundle Test (BFBT) (open access)

Cobra-IE Evaluation by Simulation of the NUPEC BWR Full-Size Fine-Mesh Bundle Test (BFBT)

The COBRA-IE computer code is a thermal-hydraulic subchannel analysis program capable of simulating phenomena present in both PWRs and BWRs. As part of ongoing COBRA-IE assessment efforts, the code has been evaluated against experimental data from the NUPEC BWR Full-Size Fine-Mesh Bundle Tests (BFBT). The BFBT experiments utilized an 8 x 8 rod bundle to simulate BWR operating conditions and power profiles, providing an excellent database for investigation of the capabilities of the code. Benchmarks performed included steady-state and transient void distribution, single-phase and two-phase pressure drop, and steady-state and transient critical power measurements. COBRA-IE effectively captured the trends seen in the experimental data with acceptable prediction error. Future sensitivity studies are planned to investigate the effects of enabling and/or modifying optional code models dealing with void drift, turbulent mixing, rewetting, and CHF.
Date: April 26, 2006
Creator: Burns, C. J. and Aumiler, D. L.
Object Type: Article
System: The UNT Digital Library
Delight2 Daylighting Analysis in Energy Plus: Integration and Preliminary User Results (open access)

Delight2 Daylighting Analysis in Energy Plus: Integration and Preliminary User Results

DElight is a simulation engine for daylight and electric lighting system analysis in buildings. DElight calculates interior illuminance levels from daylight, and the subsequent contribution required from electric lighting to meet a desired interior illuminance. DElight has been specifically designed to integrate with building thermal simulation tools. This paper updates the DElight capability set, the status of integration into the simulation tool EnergyPlus, and describes a sample analysis of a simple model from the user perspective.
Date: April 26, 2005
Creator: Carroll, William L. & Hitchcock, Robert J.
Object Type: Article
System: The UNT Digital Library
Single Transverse Mode Selectively Oxidized Vertical Cavity Lasers (open access)

Single Transverse Mode Selectively Oxidized Vertical Cavity Lasers

Vertical cavity surface emitting lasers (VCSELs) which operate in multiple transverse optical modes have been rapidly adopted into present data communication applications which rely on multi-mode optical fiber. However, operation only in the fundamental mode is required for free space interconnects and numerous other emerging VCSEL applications. Two device design strategies for obtaining single mode lasing in VCSELs based on mode selective loss or mode selective gain are reviewed and compared. Mode discrimination is attained with the use of a thick tapered oxide aperture positioned at a longitudinal field null. Mode selective gain is achieved by defining a gain aperture within the VCSEL active region to preferentially support the fundamental mode. VCSELs which exhibit greater than 3 mW of single mode output power at 850 nm with mode suppression ratio greater than 30 dB are reported.
Date: April 26, 2000
Creator: Choquette, Kent D.; Geib, Kent M.; Briggs, Ronald D.; Allerman, Andrew A. & Hindi, Jana Jo
Object Type: Article
System: The UNT Digital Library
Anisotropic intermediate valence in Yb2M3Ga9 (M = Rh, Ir) (open access)

Anisotropic intermediate valence in Yb2M3Ga9 (M = Rh, Ir)

The intermediate valence compounds Yb{sub 2}M{sub 3}Ga{sub 9} (M = Rh, Ir) exhibit an anisotropic magnetic susceptibility. We report measurements of the temperature dependence of the 4f occupation number, n{sub f}(T), for Yb{sub 2}M{sub 3}Ga{sub 9} as well as the magnetic inelastic neutron scattering spectrum S{sub mag}({Delta}E) at 12 and 300 K for Yb{sub 2}Rh{sub 3}Ga{sub 9}. Both n{sub f}(T) and S{sub mag}({Delta}E) were calculated for the Anderson impurity model with crystal field terms within an approach based on the non-crossing approximation. These results corroborate the importance of crystal field effects in these materials; they also suggest that Anderson lattice effects are important to the physics of Yb{sub 2}M{sub 3}Ga{sub 9}.
Date: April 26, 2005
Creator: Christianson, A. D.; Lawrence, J. M.; Lobos, A. M.; Aligia, A. A.; Bauer, E. D.; Moreno, N. O. et al.
Object Type: Article
System: The UNT Digital Library
Nonlinear Rayleigh-Taylor growth in convergine geometry (open access)

Nonlinear Rayleigh-Taylor growth in convergine geometry

The early nonlinear phase of Rayleigh-Taylor growth is typically described in terms of the classic Layzer model in which bubbles of light fluid rise into the heavy fluid at a constant rate determined by the bubble radius and the gravitational acceleration. However, this model is strictly valid only for planar interfaces and hence ignores any effects which might be introduced by the spherically converging interfaces of interest in inertial confinement fusion. Here a generalization of the Layzer nonlinear bubble rise rate is given for a self-similar spherically converging flow of the type studied by Kidder. A simple formula for the bubble amplitude is found showing that, while the bubble initially rises with a constant velocity similar to the Layzer result, during the late phase of the implosion, an acceleration of the bubble rise rate occurs. The bubble rise rate is verified by comparison with numerical hydrodynamics simulations.
Date: April 26, 2004
Creator: Clark, D S & Tabak, M
Object Type: Article
System: The UNT Digital Library
Control of Urania Crystallite Size by HMTA-Urea Reactions in the Internal Gelation Process for Preparing (U, Pu)O<sub>2</sub>Fuel Kernels (open access)

Control of Urania Crystallite Size by HMTA-Urea Reactions in the Internal Gelation Process for Preparing (U, Pu)O<sub>2</sub>Fuel Kernels

In the development of (U,Pu)O{sub 2} kernels by the internal gelation process for the Direct Press Spheroidized process at Oak Ridge National Laboratory, a novel crystal growth step was discovered that made it possible to prepare calcined porous kernels that could be used as direct-press feed for Fast Breeder Reactor pellet fabrication. High-quality pellets were prepared that were near theoretical density and that (upon examination) revealed no evidence of sphere remnants. The controlled crystal growth step involved using hexamethylenetetramine (HMTA)-urea stock solutions that were boiled for 60 min or less. Before this discovery, all the other crystal growth steps (when utilized) could reduce the tap density to only {approx}1.3 g/cm{sup 3}, which was not sufficiently low for use in ideal pellet pressing. The use of the boiled HMTA-urea solution allowed the tap density to be lowered to 0.93 g/cm{sup 3}, with the ideal density being about 1.0 g/cm{sup 3}. This report describes the development of this technology and its scaleup.
Date: April 26, 2005
Creator: Collins, J. L.
Object Type: Report
System: The UNT Digital Library