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Advanced Turbine System Program Phase 2 cycle selection (open access)

Advanced Turbine System Program Phase 2 cycle selection

ABB`s GT24-ATS can meet or exceed the ATS program goals with minimal risk. It requires only minor modifications to the GT24 EV/SEV combustors to meet NOx goals, without steam cooling, variable geometry, or moving parts.
Date: December 31, 1995
Creator: Latcovich, J.A. Jr.
System: The UNT Digital Library
Advanced Turbine Systems Program industrial system concept development (open access)

Advanced Turbine Systems Program industrial system concept development

Solar approached Phase II of ATS program with the goal of 50% thermal efficiency. An intercolled and recuperated gas turbine was identified as the ultimate system to meet this goal in a commercial gas turbine environment. With commercial input from detailed market studies and DOE`s ATS program, Solar redefined the company`s proposed ATS to fit both market and sponsor (DOE) requirements. Resulting optimized recuperated gas turbine will be developed in two sizes, 5 and 15 MWe. It will show a thermal efficiency of about 43%, a 23% improvement over current industrial gas turbines. Other ATS goals--emissions, RAMD (reliability, availability, maintainability, durability), cost of power--will be met or exceeded. During FY95, advanced development of key materials, combustion and component technologies proceeded to the point of acceptance for inclusion in ATS Phase III.
Date: December 31, 1995
Creator: Gates, S.
System: The UNT Digital Library
Advances in welding science and technology (open access)

Advances in welding science and technology

Over the years, welding has been more of an art than a science, but in the last few decades major advances have taken place in welding science and technology. With the development of new methodologies at the crossroads of basic and applied sciences, enormous opportunities and potential exist to develop a science-based design of composition, structure, and properties of welds with intelligent control and automation of the welding processes. In the last several decades, welding has evolved as an interdisciplinary activity requiring synthesis of knowledge from various disciplines and incorporating the most advanced tools of various basic applied sciences. A series of international conferences and other publications have covered the issues, current trends and directions in welding science and technology. In the last few decades, major progress has been made in (i) understanding physical processes in welding, (ii) characterization of microstructure and properties, and (iii) intelligent control and automation of welding. This paper describes some of these developments.
Date: December 31, 1995
Creator: David, S.A.; Babu, S.S. & Vitek, J.M.
System: The UNT Digital Library
Advancing manufacturing through computational chemistry (open access)

Advancing manufacturing through computational chemistry

The capabilities of nanotechnology and computational chemistry are reaching a point of convergence. New computer hardware and novel computational methods have created opportunities to test proposed nanometer-scale devices, investigate molecular manufacturing and model and predict properties of new materials. Experimental methods are also beginning to provide new capabilities that make the possibility of manufacturing various devices with atomic precision tangible. In this paper, we will discuss some of the novel computational methods we have used in molecular dynamics simulations of polymer processes, neural network predictions of new materials, and simulations of proposed nano-bearings and fluid dynamics in nano- sized devices.
Date: December 31, 1995
Creator: Noid, D. W.; Sumpter, B. G. & Tuzun, R. E.
System: The UNT Digital Library
Advantages of using a mirror as the first optical component for APS undulator beamlines (open access)

Advantages of using a mirror as the first optical component for APS undulator beamlines

The advantages of using a mirror as the first optical component for an APS undulator beamline for thermal management, radiation shielding mitigation, and harmonic rejection are presented.
Date: December 31, 1995
Creator: Yun, W.; Khounsary, A.M.; Lai, B.; Randall, K.J.; McNulty, I.; Gluskin, E. et al.
System: The UNT Digital Library
Aerodynamics overview of the ground transportation systems (GTS) project for heavy vehicle drag reduction (open access)

Aerodynamics overview of the ground transportation systems (GTS) project for heavy vehicle drag reduction

The focus of the research was to investigate the fundamental aerodynamics of the base flow of a tractor trailer that would prove useful in fluid flow management. Initially, industry design needs and constraints were defined. This was followed by an evaluation of state-of-the-art Navier-Stokes based computational fluid dynamics tools. Analytical methods were then used in combination with computational tools in a design process. Several geometries were tested at 1:8 scale in a low speed wind tunnel. In addition to the baseline geometry, base add-on devices of the class of ogival boattails and slants were analyzed.
Date: December 31, 1995
Creator: Gutierrez, W. T.; Hassan, B.; Croll, R. H. & Rutledge, W. H.
System: The UNT Digital Library
Aerospace modal test optimization using VETO (virtual environment for test optimization) (open access)

Aerospace modal test optimization using VETO (virtual environment for test optimization)

We present a software environment integrating analysis and test based models to support optimal modal test design of aerospace components through a Virtual Environment for Test Optimization (VETO). A goal in developing this software tool is to provide test and analysis organizations with a capability of mathematically simulating the complete test environment within a computer. Derived models of test equipment, instrumentation and hardware can be combined within the VETO to provide the user with a unique analysis and visualization capability to evaluate new and existing test methods. The VETO assists analysis and test engineers in maximizing the value of each modal test. It is particularly advantageous for structural dynamics model reconciliation applications. The VETO enables an engineer to interact with a finite element model of an aerospace component to optimally place sensors and exciters and to investigate the selection of data acquisition parameters needed to conduct a complete modal survey. Additionally, the user can evaluate the use of different types of instrumentation such as filters, amplifiers and transducers for which models are available in the VETO. The dynamic response of most of the virtual instruments (including the device under test) are modeled in the state space domain. Design of modal …
Date: December 31, 1995
Creator: Klenke, S. E.; Reese, G. M.; Schoof, L. A. & Shierling, C. L.
System: The UNT Digital Library
AGS performance and upgrades; A possible proton driver for a muon collider (open access)

AGS performance and upgrades; A possible proton driver for a muon collider

After the successful completion of the AGS Booster and several upgrades of the AGS, a new intensity record of 6.3 x 10{sup 13} protons per pulse accelerated to 24GeV was achieved. Further intensity upgrades are being discussed that could increase the average delivered beam intensity by up to a factor of six. The total beam power then reaches almost 1 MW and the AGS can then be considered as a proton driver for a muon collider.
Date: December 31, 1995
Creator: Roser, T.
System: The UNT Digital Library
The AGTSR consortium: An update (open access)

The AGTSR consortium: An update

The Advanced Gas Turbine Systems Research program is a nationwide consortium dedicated to advancing land-based gas turbine systems for improving future power generation capability. It directly supports the technology-research arm of the ATS program and targets industry- defined research needs in the areas of combustion, heat transfer, materials, aerodynamics, controls, alternative fuels, and advanced cycles. It is organized to enhance U.S. competitiveness through close collaboration with universities, government, and industry at the R&D level. AGTSR is just finishing its third year of operation; it is scheduled to continue past the year 2000. This update reviews the AGTSR triad, which consists of university/industry R&D activities, technology transfer programs, and trial student programs.
Date: December 31, 1995
Creator: Fant, D.B. & Golan, L.P.
System: The UNT Digital Library
Los Alamos National Laboratory scientific interactions with the Former Soviet Union (open access)

Los Alamos National Laboratory scientific interactions with the Former Soviet Union

The Los Alamos National Laboratory has a wide-ranging set of scientific interactions with technical institutes in the Former Soviet Union (FSU). Many of these collaborations, especially those in pure science, began long before the end of the Cold War and the breakup of the Soviet Union. This overview will, however, focus for the most part on those activities that were initiated in the last few years. This review may also serve both to indicate the broad spectrum of US government interests that are served, at least in part, through these laboratory initiatives, and to suggest ways in which additional collaborations with the FSU may be developed to serve similar mutual interests of the countries involved. While most of the examples represent programs carried out by Los Alamos, they are also indicative of similar efforts by Lawrence Livermore National Laboratory and Sandia National Laboratories. There are indeed other Department of Energy (DOE) laboratories, and many of them have active collaborative programs with FSU institutes. However, the laboratories specifically identified above are those with special nuclear weapons responsibilities, and thus have unique technical capabilities to address certain issues of some importance to the continuing interests of the United States and the states …
Date: December 31, 1995
Creator: White, P. C.
System: The UNT Digital Library
Alignment and Commissionig of the APS Beamline Front Ends (open access)

Alignment and Commissionig of the APS Beamline Front Ends

Fifteen out of forty phase-one beamline front ends have been installed in the storage-ring tunnel at the 7-GeV Advanced Photon Source (APS). For the front-end installation, a four-step alignment process was designed and consists of (1) prealigning the front-end components with support tables in the preassembly area, (2) installing the components with tables in the storage-ring tunnel and aligning relative to the APS global telescope survey network, (3) confirming the alignment using a tooling laser alignment system, and (4) performing adjustments with the synchrotron-radiation beam during commissioning. The laser alignment system and the prealignment data- base have been of great importance for the expedient maintenance of front-end components. These tools are very important to a large synchrotron radiation facility such as the APS, since they make a quick alignment setup possible and minimize alignment time inside the tunnel. This paper will present the four-step alignment process, the laser alignment system, and discuss the alignment confirmation results. 6 refs., 5 figs.
Date: December 31, 1995
Creator: Shu, D.; Barraza, J.; Ramanathan, M.; Chang, J. & Kuzay, T. M.
System: The UNT Digital Library
Allison engine ATS program technical review (open access)

Allison engine ATS program technical review

Gas turbines in industrial and utility applications can help meet future national and worldwide power generation requirements. Implementation of the ATS Program will also keep U.S. manufacturers on the cutting edge of turbine technology for power generation applications and enhance the nation`s economic competitiveness. Allison`s ATS addresses the program goals in the following manner: (1) Efficiency - The turbine selected for the ATS uses Allison`s latest single crystal alloys incorporating the most efficient component cooling technology Allison has developed. These features allow the turbine to operate at a rotor inlet temperature (RIT) of 1427{degrees}C (2600{degrees}F). The compression system for this engine has an overall pressure ratio of more than 20:1 and is based on technology previously demonstrated at Allison. The engine that uses these components will demonstrate a thermal efficiency that is 18% better than the best in class today. (2) Environment - The combustion system selected for this engine incorporates a catalytically stabilized, lean premix system with ceramic components requiring no significant wall cooling. This system will achieve acceptance in severe nonattainment areas, producing less than 8 ppm for oxides of nitrogen (NOx), with acceptable carbon monoxide (CO) and unburned hydrocarbon (UHC). (3) Fuel Flexibility - Allison has production …
Date: December 31, 1995
Creator: Mukavetz, D.
System: The UNT Digital Library
Alpha detection in pipes using an inverting membrane scintillator (open access)

Alpha detection in pipes using an inverting membrane scintillator

Characterization of surface alpha emitting contamination inside enclosed spaces such as piping systems presents an interesting radiological measurement challenge. Detection of these alpha particles from the exterior of the pipe is impossible since the alpha particles are completely absorbed by the pipe wall. Traditional survey techniques, using hand-held instruments, simply can not be used effectively inside pipes. Science and Engineering Associates, Inc. is currently developing an enhancement to its Pipe Explorer{trademark} system that will address this challenge. The Pipe Explorer{trademark} uses a unique sensor deployment method where an inverted tubular membrane is propagated through complex pipe runs via air pressure. The inversion process causes the membrane to fold out against the pipe wall, such that no part of the membrane drags along the pipe wall. This deployment methodology has been successfully demonstrated at several DOE sites to transport specially designed beta and gamma scintillation detectors into pipes ranging in length up to 250 ft. The measurement methodology under development overcomes the limitations associated with conventional hand-held survey instruments by remotely emplacing an alpha scintillator in direct contact with the interior pipe surface over the entire length to be characterized. This is accomplished by incorporating a suitable scintillator into the otherwise …
Date: December 31, 1995
Creator: Kendrick, D. T.; Cremer, C. D.; Lowry, W. & Cramer, E.
System: The UNT Digital Library
Alternative processing methods for tungsten-base composite materials (open access)

Alternative processing methods for tungsten-base composite materials

Tungsten composite materials contain large amounts of tungsten distributed in a continuous matrix phase. Current commercial materials include the tungsten-nickel-iron with cobalt replacing some or all of the iron, and also tungsten-copper materials. Typically, these are fabricated by liquid-phase sintering of blended powders. Liquid-phase sintering offers the advantages of low processing costs, established technology, and generally attractive mechanical properties. However, liquid-phase sintering is restricted to a very limited number of matrix alloying elements and a limited range of tungsten and alloying compositions. In the past few years, there has been interest in a wider range of matrix materials that offer the potential for superior composite properties. These must be processed by solid-state processes and at sufficiently low temperatures to avoid undesired reactions between the tungsten and the matrix phase. These processes, in order of decreasing process temperature requirements, include hot-isostatic pressing (HIPing), hot extrusion, and dynamic compaction. The HIPing and hot extrusion processes have also been used to improve mechanical properties of conventional liquid-phase-sintered materials. Results of laboratory-scale investigations of solid-state consolidation of a variety of matrix materials, including titanium, hafnium, nickel aluminide, and steels are reviewed. The potential advantages and disadvantages of each of the possible alternative consolidation processes …
Date: December 31, 1995
Creator: Ohriner, E. K. & Sikka, V. K.
System: The UNT Digital Library
Aluminum removal from washed sludge (open access)

Aluminum removal from washed sludge

Purpose of this project is to reduce the volume of storage tank sludge to be treated by removing the Al and other nonradioactive components. In initial sludge surrogate studies, Al, Cr, and Zn showed the highest solubility in NaOH solutions; Ce and Zr were the least soluble of the elements tested. Removal of Fe and Bi approached 2%, the rest of the elements studied showed <1% removal. Amount of Al removed increased as the NaOH conc. increased from 0.1 to 6 M. Sequential washing of the sludge surrogate with 3 M NaOH removed 84% of the Al, 39% of the Cr, and 65% of the Zn. Surrogate sludges containing U and Th were also studied.
Date: December 31, 1995
Creator: Egan, B. Z.; Collins, J. L. & Ensor, D. D.
System: The UNT Digital Library
Ammonia usage in vapor compression for refrigeration and air-conditioning in the United States (open access)

Ammonia usage in vapor compression for refrigeration and air-conditioning in the United States

The impending phaseout of CFCs and HCFCs has led to a worldwide search for refrigerants that can provide equivalent performance while not damaging the environment. Long used as a working fluid in industrial and large-scale refrigeration, ammonia provides high efficiency, low initial cost, and no detrimental impact to the environment. However, its toxicity and flammability, along with technical considerations and increased operating costs, deter its use in many refrigeration and cooling applications. Utilization of ammonia in applications where its safety considerations and technical concerns can be addressed provides the best growth opportunity for adoption as a replacement refrigerant. Applications such as district or large-scale cooling, thermal storage, packaged systems, and combined systems hold promise for increased usage of ammonia. Ongoing research and development are providing solutions to technical considerations, and innovations in safety and containment of ammonia are addressing those particular concerns, but code restrictions and regulations present the greatest barrier to wider adoption of ammonia as an alternate refrigerant in the US To encourage wider use, future efforts will need to continue on improved safety and more efficient design, along with an increased emphasis on educating and informing industry and the public about the advantages ammonia and the factors …
Date: December 31, 1995
Creator: Fairchild, P.D. & Baxter, V.D.
System: The UNT Digital Library
Analyses of residual thermal stresses in ceramic matrix composites (open access)

Analyses of residual thermal stresses in ceramic matrix composites

Residual thermal stresses in ceramic matrix composites containing either ellipsoidal inclusions or short fibers (i.e., fibers of finite length) are considered. First, the residual stresses in ellipsoidal inclusions are uniform, and they are analyzed using a modified Eshelby model. Although closed-form analytical solutions are obtained, their formulations are formidable. When the aspect ratio of the ellipsoid is 0, 1, or infinity, simple analytical solutions can be obtained using different models, and they are in excellent agreement with those obtained from the modified Eshelby model. Second, residual stresses in short fibers are nonuniform, and they are analyzed using a modified shear lag model, in which imaginary fibers are introduced to satisfy the continuity condition at the fiber ends. The analytical solutions are compared to the experimental results.
Date: December 31, 1995
Creator: Hsueh, C.H. & Becher, P.F.
System: The UNT Digital Library
Analysis of civilian processing programs in reduction of excess separated plutonium and high-enriched uranium (open access)

Analysis of civilian processing programs in reduction of excess separated plutonium and high-enriched uranium

The purpose of this preliminary investigation is to explore alternatives and strategies aimed at the gradual reduction of the excess inventories of separated plutonium and high-enriched uranium (HEU) in the civilian nuclear power industry. The study attempts to establish a technical and economic basis to assist in the formation of alternative approaches consistent with nonproliferation and safeguards concerns. The analysis addresses several options in reducing the excess separated plutonium and HEU, and the consequences on nonproliferation and safeguards policy assessments resulting from the interacting synergistic effects between fuel cycle processes and isotopic signatures of nuclear materials.
Date: December 31, 1995
Creator: Persiani, P.J.
System: The UNT Digital Library
Analysis of Exxon crude-oil-slip stream coking data (open access)

Analysis of Exxon crude-oil-slip stream coking data

Fouling of pre-heat train heat exchangers and process heaters used for the crude-distillation unit is a major unsolved problem which costs the industry in terms of energy inefficiency and productivity loss. The complexity of the fouling problem has prevented the industry from developing effective mitigation methods. Coking is a general term used for fouling at high temperatures, because the structure of the deposition resemblance to coke. Exxon Research and Engineering Co. conducted a joint research project with the US Department of Energy. One part of the research was to conduct coking experiments for crude oil subjected to heat fluxes greater than typical industrial conditions. In the present study, the coking data are re-analyzed and a simplified model is developed for predicting threshold fouling conditions. Recommendations are made for future experiments and analysis of the laboratory and field data.
Date: December 31, 1995
Creator: Ebert, W. & Panchal, C.B.
System: The UNT Digital Library
Analysis of operating costs a Low-Level Mixed Waste Incineration Facility (open access)

Analysis of operating costs a Low-Level Mixed Waste Incineration Facility

By definition, mixed wastes contain both chemically hazardous and radioactive components. These components make the treatment and disposal of mixed wastes expensive and highly complex issues because the different regulations which pertain to the two classes of contaminants frequently conflict. One method to dispose of low-level mixed wastes (LLMWs) is by incineration, which volatizes and destroys the organic (and other) hazardous contaminants and also greatly reduces the waste volume. The US Department of Energy currently incinerates liquid LLMW in its Toxic Substances Control Act (TSCA) Incinerator, located at the K-25 Site in Oak Ridge, Tennessee. This incinerator has been fully permitted since 1991 and to date has treated approximately 7 {times} 10{sup 6} kg of liquid LLMW. This paper presents an analysis of the budgeted operating costs by category (e.g., maintenance, plant operations, sampling and analysis, and utilities) for fiscal year 1994 based on actual operating experience (i.e., a ``bottoms-up`` budget). These costs provide benchmarking guidelines which could be used in comparing incinerator operating costs with those of other technologies designed to dispose of liquid LLMW. A discussion of the current upgrade status and future activities are included in this paper. Capital costs are not addressed.
Date: December 31, 1995
Creator: Loghry, S.L.; Salmon, R. & Hermes, W.H.
System: The UNT Digital Library
Analytical determination of package response to severe impact (open access)

Analytical determination of package response to severe impact

One important part of radioactive material transport risk assessments is amount of release from packages in accidents more severe than design basis accident (US NRC 10CFR71 1995). In order to remove some of the conservatism from current risk assessments, an effort is ongoing to qualify the finite element method for predicting cask performance by comparing analytical results to test measurements of the Structural Evaluation Test Unit (SETU) cask. Comparisons of deformed shapes, strains, and accelerations were made for impact velocities of 13.4, 20.1, and 26.8 m/s (30, 45, and 60 mph). The 13.4 m/s impact corresponds to the regulatory 9 m (30 ft) free fall, and the others correspond to impacts with 2.25 and 4 times the kinetic energy of the regulatory impact. One other analysis at an impact velocity of 38.0 m/s (85 mph) or 8 times regulatory impact kinetic energy was also done.
Date: December 31, 1995
Creator: Ludwigsen, J. S. & Ammerman, D. J.
System: The UNT Digital Library
Anomalous Abelian symmetry in the standard model (open access)

Anomalous Abelian symmetry in the standard model

The observed hierarchy of quark and lepton masses can be parametrized by nonrenormalizable operators with dimensions determined by an anomalous Abelian family symmetry, a gauge extension to the minimal supersymmetric standard model. Such an Abelian symmetry is generic to compactified superstring theories, with its anomalies compensated by the Green-Schwarz mechanism. If we assume these two symmetries to be the same, we find the electroweak mixing angle to be sin {sup 2}{theta}{sub {omega}} = 3/8 at the string scale, just by setting the ratio of the product of down quark to charged lepton masses equal to one at the string scale. This assumes no GUT structure. The generality of the result suggests a superstring origin for the standard model. We generalize our analysis to massive neutrinos, and mixings in the lepton sector.
Date: December 31, 1995
Creator: Ramond, P.
System: The UNT Digital Library
Apatite- and Monazite-Bearing Glass-Crystal Composites for the Immobilization of Low-level Nuclear and Hazardous Wastes (open access)

Apatite- and Monazite-Bearing Glass-Crystal Composites for the Immobilization of Low-level Nuclear and Hazardous Wastes

This study demonstrates that glass-crystal composite waste forms can be produced from waste streams containing high proportions of phosphorus, transition metals, and/or halides. The crystalline phases produced in crucible-scale melts include apatite, monazite, spinels, and a Zr-Si-Fe-Ti phase. These phases readily incorporated radionuclide and toxic metals into their crystal structures, while corrosion tests have demonstrated that glass-crystal composites can be up to 300-fold more durable than simulated high-level nuclear waste glasses, such as SRL 202U.
Date: December 31, 1995
Creator: Wronkiewicz, D.J.; Wolf, S.F. & DiSanto, T.S.
System: The UNT Digital Library
Applicability of ZPR critical experiment data to criticality safety (open access)

Applicability of ZPR critical experiment data to criticality safety

More than a hundred zero power reactor (ZPR) critical assemblies were constructed, over a period of about three decades, at the Argonne National Laboratory ZPR-3, ZPR-6, ZPR-9 and ZPPR fast critical assembly facilities. To be sure, the original reason for performing these critical experiments was to support fast reactor development. Nevertheless, data from some of the assemblies are well suited to form the basis for valuable, new criticality safety benchmarks. The purpose of this paper is to describe the ZPR data that would be of benefit to the criticality safety community and to explain how these data could be developed into practical criticality safety benchmarks.
Date: December 31, 1995
Creator: Schaefer, R.W.; Aumeier, S.E. & McFarlane, H.F.
System: The UNT Digital Library