Spatial Analysis of Emissions Sources for HCCI Combustion at Low Loads Using a Multi-Zone Model (open access)

Spatial Analysis of Emissions Sources for HCCI Combustion at Low Loads Using a Multi-Zone Model

We have conducted a detailed numerical analysis of HCCI engine operation at low loads to investigate the sources of HC and CO emissions and the associated combustion inefficiencies. Engine performance and emissions are evaluated as fueling is reduced from typical HCCI conditions, with an equivalence ratio f = 0.26 to very low loads (f = 0.04). Calculations are conducted using a segregated multi-zone methodology and a detailed chemical kinetic mechanism for iso-octane with 859 chemical species. The computational results agree very well with recent experimental results. Pressure traces, heat release rates, burn duration, combustion efficiency and emissions of hydrocarbon, oxygenated hydrocarbon, and carbon monoxide are generally well predicted for the whole range of equivalence ratios. The computational model also shows where the pollutants originate within the combustion chamber, thereby explaining the changes in the HC and CO emissions as a function of equivalence ratio. The results of this paper contribute to the understanding of the high emission behavior of HCCI engines at low equivalence ratios and are important for characterizing this previously little explored, yet important range of operation.
Date: February 20, 2004
Creator: Aceves, S. M.; Flowers, D. L.; Espinosa-Loza, F.; Martinez-Frias, J.; Dec, J. E.; Sjoberg, M. et al.
Object Type: Article
System: The UNT Digital Library
100-C water plant (open access)

100-C water plant

System curves for each portion of the C Area Water Plant were obtained from referenced work and are presented in figures. Field test data, corroborating the calculated curves, are presented as singular points on the same graphs. Present maxima capacity of the C Area Filter Plant was 121,000 gpm with 118,000 gpm available for use as primary reactor coolant. Modifications to the filter effluent piping would increase this available flow to about 180,000 gpm. Of the 118,000 gpm available for C Reactor use, 10,000 to 12,000 gpm was demanded by B Area through the 183 BC intertie. The maximum flow that the intertie line could handle, without reducing the filter capacity of the C Area filters, is about 21,000 gpm.
Date: February 20, 1961
Creator: Agar, J. D.
Object Type: Report
System: The UNT Digital Library
Search for Neutrino Oscillations at the Brookhaven AGS (open access)

Search for Neutrino Oscillations at the Brookhaven AGS

We report on a search for neutrino oscillations of the type nu/sub ..mu../ ..-->.. nu/sub e/ in a detector located an effective distance of 96m from the neutrino source in the wide band neutrino beam at the Brookhaven AGS. No excess of electron events was observed. The resulting upper limit on the strength of the mixing between nu/sub ..mu../ and nu/sub e/ in the case of large mass difference ..delta..m/sup 2/ = absolute value m/sub 1//sup 2/ - m/sub 2//sup 2/ between the neutrino mass eigenstates m/sub 1/ and m/sub 2/ is sin/sup 2/2..cap alpha.. less than or equal to 3.4 x 10/sup -3/ at 90% CL. The corresponding upper limit for small mass difference is ..delta..m/sup 2/sin2..cap alpha.. < 0.43 eV/sup 2/. 9 refs.
Date: February 20, 1985
Creator: Ahrens, L. A.; Aronson, S. H.; Connolly, P. L.; Gibbard, B. G.; Murtagh, M. J.; Murtagh, S. J. et al.
Object Type: Article
System: The UNT Digital Library
THE NUCLEAR FUEL CYCLE: PROSPECTS FOR REDUCING ITS COST (open access)

THE NUCLEAR FUEL CYCLE: PROSPECTS FOR REDUCING ITS COST

Nuclear fuel cost of 1.25 mills/kwh would make nuclear power competitive with conventional power in lowcost coal areas if capital and operating costs can be brought to within about 10 percent of those of coal-fired plants. Substantial decreases in fuel fabrication cost are anticipated by 1970: other costs in the fuel cycle are expccted to remain about the same as at present. Unit costs and irradiation levels that would be needed to give a fuel cost of 1.25 mills/kwh are believed to be attainable by 1970. (auth)
Date: February 20, 1959
Creator: Albrecht, W.L.
Object Type: Report
System: The UNT Digital Library
Space Vehicle Shielding Studies. Part Iii. The Attenuation of a Particular Solar Flare by an Aluminum Shield (open access)

Space Vehicle Shielding Studies. Part Iii. The Attenuation of a Particular Solar Flare by an Aluminum Shield

None
Date: February 20, 1964
Creator: Alsmiller, R. G., Jr. & Murphy, J. E.
Object Type: Report
System: The UNT Digital Library
The {phi} mean free path in hot hadronic matter (open access)

The {phi} mean free path in hot hadronic matter

We calculate the {phi} meson collision rate and mean free path in a hot hadronic gas. The Hidden Local Symmetry model is used to take into account interactions of {phi} mesons with pseudoscalar ({pi}, K) and vector mesons ({rho}, {omega}, K*, {phi}). In contrast to previous calculations we find a significantly small mean free path (around 1 fm at T=200MeV). This implies that {phi} mesons produced after hadronization in relativistic heavy ion collisions will not leave the collision region without scattering. The consequences of these findings to the analysis of {phi} yields are discussed.
Date: February 20, 2002
Creator: Alvarez-Ruso, Luis & Koch, Volker
Object Type: Article
System: The UNT Digital Library
Phi meson propagation in a hot hadronic gas (open access)

Phi meson propagation in a hot hadronic gas

The Hidden Local Symmetry Lagrangian is used to study the interactions of phi mesons with other pseudoscalar and vector mesons in a hadronic gas at finite temperature. We have found a significantly small phi mean free path (less than 2.4 fm at T &gt; 170 MeV) due to large collision rates with rho mesons, kaons and predominantly K* in spite of their heavy mass. This implies that phi mesons produced after hadronization in relativistic heavy ion collisions will not leave the hadronic system without scattering. The effect of these interactions on the time evolution of the phi density in the expanding hadronic fireball is investigated.
Date: February 20, 2002
Creator: Alvarez-Ruso, Luis & Koch, Volker
Object Type: Article
System: The UNT Digital Library
Recommendations to NWIG on the implementation of need-to-know access controls in an electronic information environment (open access)

Recommendations to NWIG on the implementation of need-to-know access controls in an electronic information environment

This report discusses `Recommendatins to NWIG on the Implementation of Need-To-Know Access Controls in an Electronic Information Environment`.
Date: February 20, 1997
Creator: Ames, H. S.
Object Type: Report
System: The UNT Digital Library
Conduct of operations implementation plan (open access)

Conduct of operations implementation plan

This implementation plan describes the process and provides information and schedules that are necessary to implement and comply with the Department of Energy (DOE) Order 5480.19, {open_quotes}Conduct of Operations{close_quotes} (CoOp). This plan applies to all Pinellas Plant operations and personnel. Generally, this Plan discusses how DOE Order 5480.19 will be implemented at the Pinellas Plant.
Date: February 20, 1991
Creator: Anderson, Christie K. & Hall, Raymond L.
Object Type: Report
System: The UNT Digital Library
FY 2007 Miniature Spherical Retroreflectors Final Report (open access)

FY 2007 Miniature Spherical Retroreflectors Final Report

Miniature spherical retroreflectors, less than 8 millimeters in diameter, are currently being developed to enhance remote optical detection of nuclear proliferation activities. These retroreflecting spheres resemble small, sand-colored marbles that have the unique optical property of providing a strong reflection directly back to the source (i.e., retroreflecting) when illuminated with a laser. The addition of specific coatings, sensitive to specific chemicals or radioactive decay in the environment, can be applied to the surface of these retroreflectors to provide remote detection of nuclear proliferation activities. The presence of radioactive decay (e.g., alpha, gamma, neutron) or specific chemicals in the environment (e.g., TBP, acids) will change the optical properties of the spheres in a predictable fashion, thus indicating the presence or absence of the target materials. One possible scenario might employ an airborne infrared laser system (e.g., quantum-cascade lasers) to illuminate a section of ground littered with these retroreflective spheres. Depending on the coating and the presence of a specific chemical or radioisotope in the environment, the return signal would be modified in some predictable fashion because of fluorescence, frequency shifting, intensity attenuation/enhancement, or change in polarization. Research conducted in FY 2007 focused on developing novel optical fabrication processes and exploiting the …
Date: February 20, 2008
Creator: Anheier, Norman C.; Bernacki, Bruce E. & Krishnaswami, Kannan
Object Type: Report
System: The UNT Digital Library
Preoperational Subsurface Conditions at the Idaho Nuclear Technology and Engineering Center Service Wastewater Discharge Facility (open access)

Preoperational Subsurface Conditions at the Idaho Nuclear Technology and Engineering Center Service Wastewater Discharge Facility

The Idaho Nuclear Technology and Engineering Center (INTEC) Service Wastewater Discharge Facility replaces the existing percolation ponds as a disposal facility for the INTEC Service Waste Stream. A preferred alternative for helping decrease water content in the subsurface near INTEC, closure of the existing ponds is required by the INTEC Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Record of Decision (ROD) for Waste Area Group 3 Operable Unit 3-13 (DOE-ID 1999a). By August 2002, the replacement facility was constructed approximately 2 miles southwest of INTEC, near the Big Lost River channel. Because groundwater beneath the Idaho National Engineering and Environmental Laboratory (INEEL) is protected under Federal and State of Idaho regulations from degradation due to INEEL activities, preoperational data required by U.S. Department of Energy (DOE) Order 5400.1 were collected. These data include preexisting physical, chemical, and biological conditions that could be affected by the discharge; background levels of radioactive and chemical components; pertinent environmental and ecological parameters; and potential pathways for human exposure or environmental impact. This document presents specific data collected in support of DOE Order 5400.1, including: four quarters of groundwater sampling and analysis of chemical and radiological parameters; general facility description; site specific geology, stratigraphy, …
Date: February 20, 2002
Creator: Ansley, Shannon L.
Object Type: Report
System: The UNT Digital Library
Computed Tomography software and standards (open access)

Computed Tomography software and standards

This document establishes the software design, nomenclature, and conventions for industrial Computed Tomography (CT) used in the Nondestructive Evaluation Section at Lawrence Livermore National Laboratory. It is mainly a users guide to the technical use of the CT computer codes, but also presents a proposed standard for describing CT experiments and reconstructions. Each part of this document specifies different aspects of the CT software organization. A set of tables at the end describes the CT parameters of interest in our project. 4 refs., 6 figs., 1 tab.
Date: February 20, 1990
Creator: Azevedo, S. G.; Martz, H. E.; Skeate, M. F.; Schneberk, D. J. & Roberson, G. P.
Object Type: Report
System: The UNT Digital Library
Fabrication of large diameter alumino-silicate K{sup +} sources (open access)

Fabrication of large diameter alumino-silicate K{sup +} sources

Alumino-silicate K{sup +} sources have been used in HIF experiments for many years. For example the Neutralized Transport Expt. (NTX) and the High Current Transport Expt. (HCX) are now using this type of ion source with diameters of 2.54 cm and 10 cm respectively. These sources have demonstrated ion currents of 80 mA and 700 mA, for typical HIF pulse lengths of 5-10 {micro}s. The corresponding current density is {approx} 10-15 mA/cm{sup 2}, but much higher current density has been observed using smaller size sources. Recently we have improved our fabrication techniques and, therefore, are able to reliably produce large diameter ion sources with high quality emitter surface without defects. This note provides a detailed description of the procedures employed in the fabrication process. The variables in the processing steps affecting surface quality, such as substrate porosity, powder size distribution, coating technique on large area concave surfaces, drying, and heat firing temperature have been investigated.
Date: February 20, 2003
Creator: Baca, D.; Chacon-Golcher, E.; Kwan, J. W. & Wu, J. K.
Object Type: Article
System: The UNT Digital Library
HEAT OF DILUTION CALCULATION FOR 19 MOLAR SODIUM HYDROXIDE WITH WATER FOR USE IN 241-S-112 (open access)

HEAT OF DILUTION CALCULATION FOR 19 MOLAR SODIUM HYDROXIDE WITH WATER FOR USE IN 241-S-112

High concentration caustic solutions are known to cause stress corrosion cracking in carbon steel at elevated temperature. This calculation establishes the conditions where heat of dilution will not cause the solution temperature--concentration to exceed the boundary for stress corrosion cracking as established by NACE International.
Date: February 20, 2007
Creator: Barton, W. B.
Object Type: Report
System: The UNT Digital Library
Equivalent circuit analysis of multiperiodic structures (open access)

Equivalent circuit analysis of multiperiodic structures

None
Date: February 20, 1973
Creator: Bauer, W.
Object Type: Report
System: The UNT Digital Library
Computational physical oceanography -- A comprehensive approach based on generalized CFD/grid techniques for planetary scale simulations of oceanic flows. Final report, September 1, 1995--August 31, 1996 (open access)

Computational physical oceanography -- A comprehensive approach based on generalized CFD/grid techniques for planetary scale simulations of oceanic flows. Final report, September 1, 1995--August 31, 1996

The original intention for this work was to impart the technology that was developed in the field of computational aeronautics to the field of computational physical oceanography. This technology transfer involved grid generation techniques and solution procedures to solve the governing equations over the grids thus generated. Specifically, boundary fitting non-orthogonal grids would be generated over a sphere taking into account the topography of the ocean floor and the topography of the continents. The solution methodology to be employed involved the application of an upwind, finite volume discretization procedure that uses higher order numerical fluxes at the cell faces to discretize the governing equations and an implicit Newton relaxation technique to solve the discretized equations. This report summarizes the efforts put forth during the past three years to achieve these goals and indicates the future direction of this work as it is still an ongoing effort.
Date: February 20, 1997
Creator: Beddhu, M.; Jiang, M.Y.; Whitfield, D.L.; Taylor, L.K. & Arabshahi, A.
Object Type: Report
System: The UNT Digital Library
High-resolution crystal spectrometer for the 10-60 (angstrom) EUV region (open access)

High-resolution crystal spectrometer for the 10-60 (angstrom) EUV region

A vacuum crystal spectrometer with nominal resolving power approaching 1000 is described for measuring emission lines with wavelength in the extreme ultraviolet region up to 60 Angstroms. The instrument utilizes a flat octadecyl hydrogen maleate (OHM) crystal and a thin-window 1-D position-sensitive gas proportional detector. This detector employs a 1 {micro}m-thick 100 x8 mm{sup 2} aluminized polyimide window and operates at one atmosphere pressure. The spectrometer has been implemented on the Livermore electron beam ion traps. The performance of the instrument is illustrated in measurements of the newly discovered magnetic field-sensitive line in Ar{sup 8+}.
Date: February 20, 2004
Creator: Beiersdorfer, P; Brown, G V; Goddard, R & Wargelin, B J
Object Type: Article
System: The UNT Digital Library
Numerical results of PT IP-412-AI, B and C reactors export system test (open access)

Numerical results of PT IP-412-AI, B and C reactors export system test

The purpose of this document is to present the numerical results of a production test of the last ditch water backup system performed at B and C reactors on December 15, 1961. The main purpose of the production test was to determine more accurately the capacity of the export system for supplying flow to a dual reactor area under several simulated emergency conditions where BPA power to all areas has been interrupted and the steam supply to one old area has been lost. In addition, the flow capacity of the high tanks to,the reactor was tested alone and in parallel with the export system, and the action of the surge suppressors at all areas was recorded when cycling of the surge suppressors was deliberately induced.
Date: February 20, 1962
Creator: Benson, J. L.
Object Type: Report
System: The UNT Digital Library
The Relationship Between the Surface Appearance and Depth of Damage of Subfabric and Bare Skin Burns Produced by Radiant Thermal Energy (open access)

The Relationship Between the Surface Appearance and Depth of Damage of Subfabric and Bare Skin Burns Produced by Radiant Thermal Energy

In a series of 600 cutaneous burns in swine produced by radiant thermal energy at 0.5 and 5.0 sec exposure time, the relationship of thc surface appearance and the depth of damage of bare skin and subfabric burns was investigated. The fabrics used were a black and a gray sateen weighing 8 to 9 oz/ yd/sup 2/. It was found that there is no significant difference in the 1+ burns whether produced on bare skin or beneath fabric, either at 0.5 or 5.0 sec exposure. However, the 2+ subfabric burns average about 0.1 mm deeper in dermal damage than thc same grade barn of bare skin. Nevertheless, the protection afforded by fabric is found to be nearly the same whether the burns were judged by surface appearance or microscopically by depth of damage. (auth)
Date: February 20, 1958
Creator: Berkley, K. M.
Object Type: Report
System: The UNT Digital Library
Three-Loop Superfiniteness of N=8 Supergravity (open access)

Three-Loop Superfiniteness of N=8 Supergravity

We construct the three-loop four-point amplitude of N = 8 supergravity using the unitarity method. The amplitude is ultraviolet finite in four dimensions. Novel cancellations, not predicted by traditional superspace power-counting arguments, render its degree of divergence in D dimensions to be no worse than that of N = 4 super-Yang-Mills theory--a finite theory in four dimensions. Similar cancellations can be identified at all loop orders in certain unitarity cuts, suggesting that N = 8 supergravity may be a perturbatively finite theory of quantum gravity.
Date: February 20, 2007
Creator: Bern, Z.; Carrasco, J.J.; Dixon, L.J.; Johansson, H.; Kosower, D.A. & Roiban, R.
Object Type: Article
System: The UNT Digital Library
Evaluation, design, development, and delivery of a 1200-kV prototype termination. Eighth technical progress report, September 1-November 30, 1980 (open access)

Evaluation, design, development, and delivery of a 1200-kV prototype termination. Eighth technical progress report, September 1-November 30, 1980

Tests are continuing on the shatter-resistant weathercase models and small samples. Extensive studies of composite materials has resulted in characterization of the epoxy weathercase materials mechanical properties over a wide range of temperatures and lifetime. Progress is reported on the design of the full scale prototype termination.
Date: February 20, 1981
Creator: Billings, J S; Meyer, J R & Kolano, F J
Object Type: Report
System: The UNT Digital Library
The Physical Renormalization of Quantum Field Theories (open access)

The Physical Renormalization of Quantum Field Theories

The profound revolutions in particle physics likely to emerge from current and future experiments motivates an improved understanding of the precise predictions of the Standard Model and new physics models. Higher order predictions in quantum field theories inevitably requires the renormalization procedure, which makes sensible predictions out of the naively divergent results of perturbation theory. Thus, a robust understanding of renormalization is crucial for identifying and interpreting the possible discovery of new physics. The results of this thesis represent a broad set of investigations in to the nature of renormalization. The author begins by motivating a more physical approach to renormalization based on gauge-invariant Green's functions. The resulting effective charges are first applied to gauge coupling unification. This approach provides an elegant formalism for understanding all threshold corrections, and the gauge couplings unify in a more physical manner compared to the usual methods. Next, the gauge-invariant three-gluon vertex is studied in detail, revealing an interesting and rich structure. The effective coupling for the three-gluon vertex, {alpha}(k{sub 1}{sup 2}, k{sub 2}{sup 2}, k{sub 3}{sup 2}), depends on three momentum scales and gives rise to an effective scale Q{sub eff}{sup 2}(k{sub 1}{sup 2}, k{sub 2}{sup 2}, k{sub 3}{sup 2}) which governs the …
Date: February 20, 2007
Creator: Binger, Michael William.
Object Type: Report
System: The UNT Digital Library
Estimating Filtering Errors Using the Peano Kernel Theorem (open access)

Estimating Filtering Errors Using the Peano Kernel Theorem

The Peano Kernel Theorem is introduced and a frequency domain derivation is given. It is demonstrated that the application of this theorem yields simple and accurate formulas for estimating the error introduced into a signal by filtering it to reduce noise.
Date: February 20, 2009
Creator: Blair, Jerome
Object Type: Article
System: The UNT Digital Library
An investigation of the resistance rise and power fade in high-power Li-ion cells. (open access)

An investigation of the resistance rise and power fade in high-power Li-ion cells.

Two different cell chemistries, Gen 1 and Gen 2, were subjected to accelerated aging experiments. In Gen 1 calendar-life experiments, useful cell life was strongly affected by temperature and time. Higher temperatures accelerated the degradation of cell performance. The rates of resistance increase and power fade followed simple laws based on a power of time and Arrhenius kinetics. The data have been modeled using these two concepts, and the calculated data agree well with the experimental values. The Gen 1 calendar-life resistance increase and power fade data follow (time){sup 1/2} kinetics. This may be due to solid electrolyte interface (SEI) layer growth. From the cycle-life experiments, the resistance increase data also follow (time){sup 1/2} kinetics. But there is an apparent change in overall power fade mechanism going from 3% to 6% {Delta}SOC. Here, the power of time changes to a value less than 0.5, indicating that the power fade mechanism is more complex than layer growth. The Gen 2 calendar- and cycle-life experiments show the effect of cell chemistry on kinetics. The calendar-life resistance and power fade follow either linear or linear plus (time){sup 1/2} kinetics, depending on temperature. Temperature dependence for the kinetic law was also found in the …
Date: February 20, 2002
Creator: Bloom, I.; Jones, S. A.; Battaglia, V. S.; Polzin, E. G.; Henriksen, G. L.; Motloch, C. G. et al.
Object Type: Article
System: The UNT Digital Library