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NIF laser bundle review. Final report

Description: We performed additional bundle review effort subsequent to the completion of the preliminary report and are revising our original recommendations. We now recommend that the NIF baseline laser bundle size be changed to the 4x2 bundle configuration. There are several 4x2 bundle configurations that could be constructed at a cost similar to that of the baseline 4x12 (from $11M more to about $11M less than the baseline; unescalated, no contingency) and provide significant system improvements. We recommend that the building cost estimates (particularly for the in-line building options) be verified by an architect/engineer (A/E) firm knowledgeable about building design. If our cost estimates of the in-line building are accurate and therefore result in a change from the baseline U-shaped building layout, the acceptability of the in-line configuration must be reviewed from an operations viewpoint. We recommend that installation, operation, and maintenance of all laser components be reviewed to better determine the necessity of aisles, which add to the building cost significantly. The need for beam expansion must also be determined since it affects the type of bundle packing that can be used and increases the minimum laser bay width. The U-turn laser architecture (if proven viable) offers a reduction in building costs since this laser design is shorter than the baseline switched design and requires a shorter laser bay.
Date: September 15, 1995
Creator: Tietbohl, G.L.; Larson, D.W. & Erlandson, A.C.
Partner: UNT Libraries Government Documents Department

Analysis of Events Associated with First Charge of Desicooler Material

Description: HB-Line's mission included dissolution of uranium-aluminum scrap left over from a U3O8 scrap recovery program begun in 1972 with material returned from Rocky Flats and Oak Ridge. This material has been stored in desicooler containers, and is commonly referred to as the Desicoolers. The Scrap Recovery process includes the dissolution of scrap material and transfer of the resulting solution to H-Canyon for further disposition. During the first charge of this material into the HB-Line dissolvers, the solution heated to boiling without external heat being added. Yellow-colored fumes, which dissipated rapidly, were noted in the glovebox by operators, and a small amount of liquid was noted in the glovebox by operations after dissolver cooldown. This technical report documents analysis of the data from the event with respect to potential Safety Basis violation and the Integrated Safety Management System process. Based on the analysis presented, the safety basis has shown its ability to protect the worker, the facility and the public.
Date: September 15, 2003
Creator: Alexander, D.E.
Partner: UNT Libraries Government Documents Department

Grid-based Parallel Data Streaming Implemented for the Gyrokinetic Toroidal Code

Description: We have developed a threaded parallel data streaming approach using Globus to transfer multi-terabyte simulation data from a remote supercomputer to the scientist's home analysis/visualization cluster, as the simulation executes, with negligible overhead. Data transfer experiments show that this concurrent data transfer approach is more favorable compared with writing to local disk and then transferring this data to be post-processed. The present approach is conducive to using the grid to pipeline the simulation with post-processing and visualization. We have applied this method to the Gyrokinetic Toroidal Code (GTC), a 3-dimensional particle-in-cell code used to study microturbulence in magnetic confinement fusion from first principles plasma theory.
Date: September 15, 2003
Creator: Klasky, S.; Ethier, S.; Lin, Z.; Martins, K.; McCune, D. & Samtaney, R.
Partner: UNT Libraries Government Documents Department

MICROBIAL TRANSFORMATIONS OF URANIUM COMPLEXED WITH ORGANIC AND INORGANIC LIGANDS.

Description: Biotransformation of various chemical forms of uranium present in wastes, contaminated soils and materials by microorganisms under different process conditions such as aerobic and anaerobic (denitrifying, iron-reducing, fermentative, and sulfate-reducing) conditions will affect the solubility, bioavailability, and mobility of uranium in the natural environment. Fundamental understanding of the mechanisms of microbial transformations of uranium under a variety of environmental conditions will be useful in developing appropriate remediation and waste management strategies as well as predicting the microbial impacts on the long-term stewardship of contaminated sites.
Date: September 15, 2002
Creator: FRANCIS,A.J.
Partner: UNT Libraries Government Documents Department

Progress in the study of mesh refinement for particle-in-cell plasma simulations and its application to heavy ion fusion

Description: The numerical simulation of the driving beams in a heavy ion fusion power plant is a challenging task, and, despite rapid progress in computer power, one must consider the use of the most advanced numerical techniques. One of the difficulties of these simulations resides in the disparity of scales in time and in space which must be resolved. When these disparities are in distinctive zones of the simulation region, a method which has proven to be effective in other areas (e.g. fluid dynamics simulations) is the Adaptive-Mesh-Refinement (AMR) technique. We follow in this article the progress accomplished in the last few months in the merging of the AMR technique with Particle-In-Cell (PIC) method. This includes a detailed modeling of the Lampel-Tiefenback solution for the one-dimensional diode using novel techniques to suppress undesirable numerical oscillations and an AMR patch to follow the head of the particle distribution. We also report new results concerning the modeling of ion sources using the axisymmetric WARPRZ-AMR prototype showing the utility of an AMR patch resolving the emitter vicinity and the beam edge.
Date: September 15, 2002
Creator: Vay, J.-L.; Friedman, A. & Grote, D.P.
Partner: UNT Libraries Government Documents Department

Fiber-Optic Laser Raman Spectroscopy Sensor

Description: The Defense Programs Plant Directed Research and Development Program sponsored the optimization and interface of a fiber-optic Raman sensor as a complementary technique to mass spectrometry currently used in the Tritium Facility for measuring hydrogen isotopes. This sensor will provide real-time feedback while reducing the sample load for off-line gas analysis by the Tritium mass spectrometers. The compact Raman system incorporates a 488 nanometer laser system, spectrometer and detector along with a 20-foot fiber-optic probe. The analysis of gas mixtures of protium and deuterium at various compositions and total pressures ranging form 11 to 5000 torr showed good signal to noise ratios using very short integration times (15 seconds). The detection limits for protium and deuterium ranged from 0.5 percent to 0.8 percent. This probe will be demonstrated in-line in the new HT TCAP (hydrogen-tritium thermal cycling absorption process) cold runs.
Date: September 15, 2003
Creator: Ziegler, K.E.
Partner: UNT Libraries Government Documents Department

Microchannel Heat Exchangers with Carbon Dioxide

Description: The objective of the present study was to determine the performance of CO{sub 2} microchannel evaporators and gas coolers in operational conditions representing those of residential heat pumps. A set of breadboard prototype microchannel evaporators and gas coolers was developed and tested. The refrigerant in the heat exchangers followed a counter cross-flow path with respect to the airflow direction. The test conditions corresponded to the typical operating conditions of residential heat pumps. In addition, a second set of commercial microchannel evaporators and gas coolers was tested for a less comprehensive range of operating conditions. The test results were reduced and a comprehensive data analysis, including comparison with the previous studies in this field, was performed. Capacity and pressure drop of the evaporator and gas cooler for the range of parameters studied were analyzed and are documented in this report. A gas cooler performance prediction model based on non-dimensional parameters was also developed and results are discussed as well. In addition, in the present study, experiments were conducted to evaluate capacities and pressure drops for sub-critical CO{sub 2} flow boiling and transcritical CO{sub 2} gas cooling in microchannel heat exchangers. An extensive review of the literature failed to indicate any previous systematic study in this area, suggesting a lack of fundamental understanding of the phenomena and a lack of comprehensive data that would quantify the performance potential of CO{sub 2} microchannel heat exchangers for the application at hand. All experimental tests were successfully conducted with an energy balance within {+-}3%. The only exceptions to this were experiments at very low saturation temperatures (-23 C), where energy balances were as high as 10%. In the case of evaporators, it was found that a lower saturation temperature (especially when moisture condensation occurs) improves the overall heat transfer coefficient significantly. However, under such conditions, ...
Date: September 15, 2001
Creator: Zhao, Y.; Ohadi, M.M. & Radermacher, R.
Partner: UNT Libraries Government Documents Department

Advanced pressurized water reactor for improved resource utilization, part II - composite advanced PWR concept

Description: This report evaluates the enhanced resource utilization in an advanced pressurized water reactor (PWR) concept using a composite of selected improvements identified in a companion study. The selected improvements were in the areas of reduced loss of neutrons to control poisons, reduced loss of neutrons in leakage from the core, and improved blanket/reflector concepts. These improvements were incorporated into a single composite advanced PWR. A preliminary assessment of resource requirements and costs and impact on safety are presented.
Date: September 15, 1981
Creator: Turner, S.E.; Gurley, M.K.; Kirby, K.D. & Mitchell, W III
Partner: UNT Libraries Government Documents Department

Collaboration tools for the global accelerator network: Workshop Report

Description: The concept of a ''Global Accelerator Network'' (GAN) has been put forward as a means for inter-regional collaboration in the operation of internationally constructed and operated frontier accelerator facilities. A workshop was held to allow representatives of the accelerator community and of the collaboratory development community to meet and discuss collaboration tools for the GAN environment. This workshop, called the Collaboration Tools for the Global Accelerator Network (GAN) Workshop, was held on August 26, 2002 at Lawrence Berkeley National Laboratory. The goal was to provide input about collaboration tools in general and to provide a strawman for the GAN collaborative tools environment. The participants at the workshop represented accelerator physicists, high-energy physicists, operations, technology tool developers, and social scientists that study scientific collaboration.
Date: September 15, 2002
Creator: Agarwal, Deborah; Olson, Gary & Olson, Judy
Partner: UNT Libraries Government Documents Department

Constructing Integrable High-pressure Full-current Free-boundary Stellarator Magnetohydrodynamic Equilibrium Solutions

Description: For the (non-axisymmetric) stellarator class of plasma confinement devices to be feasible candidates for fusion power stations it is essential that, to a good approximation, the magnetic field lines lie on nested flux surfaces; however, the inherent lack of a continuous symmetry implies that magnetic islands responsible for breaking the smooth topology of the flux surfaces are guaranteed to exist. Thus, the suppression of magnetic islands is a critical issue for stellarator design, particularly for small aspect ratio devices. Pfirsch-Schluter currents, diamagnetic currents, and resonant coil fields contribute to the formation of magnetic islands, and the challenge is to design the plasma and coils such that these effects cancel. Magnetic islands in free-boundary high-pressure full-current stellarator magnetohydrodynamic equilibria are suppressed using a procedure based on the Princeton Iterative Equilibrium Solver [Reiman and Greenside, Comp. Phys. Comm. 43 (1986) 157] which iterate s the equilibrium equations to obtain the plasma equilibrium. At each iteration, changes to a Fourier representation of the coil geometry are made to cancel resonant fields produced by the plasma. The changes are constrained to preserve certain measures of engineering acceptability and to preserve the stability of ideal kink modes. As the iterations continue, the coil geometry and the plasma simultaneously converge to an equilibrium in which the island content is negligible, the plasma is stable to ideal kink modes, and the coils satisfy engineering constraints. The method is applied to a candidate plasma and coil design for the National Compact Stellarator Experiment [Reiman, et al., Phys. Plasmas 8 (May 2001) 2083].
Date: September 15, 2003
Creator: Hudson, S.R.; Monticello, D.A.; Reiman, A.H.; Strickler, D.J.; Hirshman, S.P.; Ku, L-P. et al.
Partner: UNT Libraries Government Documents Department

Supersymmetric Higgs Boson Pair Production: Discovery Prospects at Hadron Colliders

Description: We study the potential of hadron colliders in the search for the pair production of neutral Higgs bosons in the framework of the Minimal Supersymmetric Standard Model. We perform a detailed signal and background analysis, working out efficient kinematical cuts for the extraction of the signal. The important role of squark loop contributions to the signal is re-emphasized. If the signal is sufficiently enhanced by these contributions, it could even be observable at the next run of the upgraded Tevatron collider in the near future. At the LHC the pair production of light and heavy Higgs bosons might be detectable simultaneously.
Date: September 15, 1999
Creator: Mizukoahi, Jose K.
Partner: UNT Libraries Government Documents Department

Supporting document for the Southeast Quadrant historical tank content estimate report for AN-Tank Farm. Vols. I and II

Description: Historical Tank Content Estimate of the Southeast Quadrant provides historical evaluations on a tank by tank basis of the radioactive mixed wastes stored in the underground double-shell tanks of the Hanford 200 East and West Areas. This report summarizes historical information such as waste history, temperature profiles, psychrometric data, tank integrity, inventory estimates and tank level history on a tank by tank basis. Tank Farm aerial photos and in- tank photos of each tank are provided. A brief description of instrumentation methods used for waste tank surveillance are included. Components of the data management effort, such as Waste Status and Transaction Record Summary, Tank Layer Model, Supernatant Mixing Model, Defined Waste Types, and Inventory Estimates which generate these tank content estimates, are also given in this report.
Date: September 15, 1995
Creator: Brevick, C.H.; Gaddis, L.A. & Consort, S.D.
Partner: UNT Libraries Government Documents Department

Application of system simulation for engineering the technical computing environment of the Lawrence Livermore National Laboratorie

Description: This report summarizes an investigation performed by Lawrence Livermore National Laboratory´┐Ż s (LLNL) Scientific Computing & Communications Department (SCCD) and the Garland Location of Raytheon Systems Company (RSC) from April through August.1998. The study assessed the applicability and benefits of utilizing System Simulation in architecting and deploying technical computing assets at LLNL, particularly in support of the ASCI program and associated scientific computing needs. The recommendations and other reported findings reflect the consensus of the investigation team. The investigation showed that there are potential benefits to performing component level simulation within SCCD in support of the ASCI program. To illustrate this, a modeling exercise was conducted by the study team that generated results consistent with measured operational performance. This activity demonstrated that a relatively modest effort could improve the toolset for making architectural trades and improving levels of understanding for managing operational practices. This capability to evaluate architectural trades was demonstrated by evaluating some of the productivity impacts of changing one of the design parameters of an existing file transfer system. The use of system simulation should be tailored to the local context of resource requirements/limitations, technology plans/processes/issues, design and deployment schedule, and organizational factors. In taking these matters into account, we recommend that simulation modeling be employed within SCCD on a limited basis for targeted engineering studies, and that an overall performance engineering program be established to better equip the Systems Engineering organization to direct future architectural decisions and operational practices. The development of an end-to-end modeling capability and enterprise-level modeling system within SCCD is not warranted in view of the associated development requirements and difficulty in determining firm operational performance requirements in advance of the critical architectural decisions. These recommendations also account for key differences between the programmatic and institutional environments at LLNL and RSC.
Date: September 15, 1998
Creator: Boyd, V; Edmunds, T; Minuzzo, K; Powell, E & Roche, L
Partner: UNT Libraries Government Documents Department

A hybrid vehicle evaluation code and its application to vehicle design. Revision 1

Description: This paper describes a hybrid vehicle simulation model which can be applied to many of the vehicles currently being considered for low pollution and high fuel economy. The code operates in batch mode with all the vehicle information stored in data files. The code calculates fuel economy for three driving schedules, time for 0--96 km/h at maximum acceleration, hill climbing performance, power train dimensions, and pollution generation rates. This paper also documents the application of the code to a hybrid vehicle that utilizes a hydrogen internal combustion engine. The simulation model is used for parametric studies of the vehicle. The results show the fuel economy of the vehicle as a function of vehicle mass, aerodynamic drag, engine efficiency, accessory load, and flywheel efficiency. The code also calculates the minimum flywheel energy and power to obtain a desired performance. The hydrogen hybrid vehicle analyzed in the paper has a predicted range of 480 km (300 miles), with a gasoline equivalent fuel efficiency of 34.2 km/liter (80.9 mpg).
Date: September 15, 1994
Creator: Aceves, S.M. & Smith, J.R.
Partner: UNT Libraries Government Documents Department

Alignment and micro-inspection system

Description: A video microscope system has been designed and installed in the C-tank, a 3-g, high-explosive firing chamber in HEAF (High Explosives Applications Facility in LLNL). This microscope system helps a great deal, not only for precision alignment of the laser beam on the minute target for the Fabry-Perot velocimeter, but also for in situ inspection of the target before and after the experiment. In addition, the video information can also be stored in the PC computer as database documentati
Date: September 15, 1998
Creator: Chau, H; Hodgin, R L & Moua, K
Partner: UNT Libraries Government Documents Department

Managing America's solid waste

Description: This report presents an historical overview of the federal role in municipal solid waste management from 1965 to approximately 1995. Attention is focuses on the federal role in safeguarding public health, protecting the environment, and wisely using material and energy resources. It is hoped that this report will provide important background for future municipal solid waste research and development initiatives.
Date: September 15, 1998
Creator: Phillips, J. A.
Partner: UNT Libraries Government Documents Department

Kinetics of Mn-based sorbents for hot coal gas desulfurization. Quarterly progress report, July 15, 1995--September 15, 1995

Description: The Morgantown Energy Technology Center (METC) of the U.S. Department of Energy (DOE) is actively pursuing the development of reliable and cost-effective processes to clean coal gasifier gases for application to integrated gasification combined cycle (IGCC) and molten carbonate fuel cell (MCFC) power plants. A large portion of gas cleanup research has been directed towards hot gas desulfurization using Zn-based sorbents. However, zinc titinate sorbents undergo reduction to the metal at temperatures approaching 700{degrees}C. In addition, sulfate formation during regeneration leads to spalling of reactive 293 surfaces. Due to zinc-based sorbent performance, METC has shown interest in formulating and testing manganese-based sorbents. Westmoreland and Harrison evaluated numerous candidate sulfur sorbents and identified Mn as a good candidate. Later, Turkdogan and Olsson tested manganese-based sorbents which demonstrated superior desulfurization capacity under high temperatures, and reducing conditions. Recently, Ben-Slimane and Hepworth conducted several studies on formulating Mn-sorbents and desulfurizing a simulated fuel gas. Although thermodynamics predicts higher over-pressures with Mn verses Zn, under certain operating conditions Mn-based sorbents may obtain < 20 ppmv. In addition, the manganese-sulfur-oxygen (Mn-S-O) system does not reduce to the metal under even highly reducing gases at high temperatures (550-900{degrees}C). Currently, many proposed IGCC processes include a water quench prior to desulfurization. This is for two reasons; limitations in the process hardware (1000{degrees}C), and excessive Zn-based sorbent loss (about 700{degrees}C). With manganese the water quench is obviated due to sorbent loss, as Mn-based sorbents have been shown to retain reactivity under cycling testing at 900{degrees}C. This reduces system hardware, and increases thermal efficiency while decreasing the equilibrium H{sub 2}S over-pressure obtainable with a manganese sorbent.
Date: September 15, 1995
Creator: Hepworth, M.T.
Partner: UNT Libraries Government Documents Department

Integrated ground-based and remotely sensed data to support global studies of environmental change

Description: Data centers routinely archive and distribute large databases of high quality and with rigorous documentation but, to meet the needs of global studies effectively and efficiently, data centers must go beyond these traditional roles. Global studies of environmental change require integrated databases of multiple data types that are accurately coordinated in terms of spatial, temporal and thematic properties. Such datasets must be designed and developed jointly by scientific researchers, computer specialists, and policy analysts. The presentation focuses on our approach for organizing data from ground-based research programs so that the data can be linked with remotely sensed data and other map data into integrated databases with spatial, temporal, and thematic characteristics relevant to global studies. The development of an integrated database for Net Primary Productivity is described to illustrate the process.
Date: September 15, 1994
Creator: Olson, R.J.; Turner, R.S. & Garten, C.T.
Partner: UNT Libraries Government Documents Department

Safety evaluation for packaging (onsite) for cesium chloride capsules with type W overpacks

Description: This Safety Evaluation for Packaging (SEP) documents the evaluation of a new basket design and overpacked cesium chloride capsule payload for the Beneficial Uses Shipping System (BUSS) Cask in accordance with the onsite transportation requirements of the Hazardous Material Packaging and Shipping manual, WHC-CM-2-14. This design supports the one-time onsite shipment of 16 cesium chloride capsules with Type W overpacks from the 324 Building to the 224T Building at the Waste Encapsulation and Storage Facility (WESF). The SEP is valid for a one-time onsite shipment or until August 1, 1998, whichever occurs first.
Date: September 15, 1997
Creator: McCoy, J.C.
Partner: UNT Libraries Government Documents Department

Operability test report for core sample truck {number_sign}1 flammable gas modifications

Description: This report primarily consists of the original test procedure used for the Operability Testing of the flammable gas modifications to Core Sample Truck No. One. Included are exceptions, resolutions, comments, and test results. This report consists of the original, completed, test procedure used for the Operability Testing of the flammable gas modifications to the Push Mode Core Sample Truck No. 1. Prior to the Acceptance/Operability test the truck No. 1 operations procedure (TO-080-503) was revised to be more consistent with the other core sample truck procedures and to include operational steps/instructions for the SR weather cover pressurization system. A draft copy of the operations procedure was used to perform the Operability Test Procedure (OTP). A Document Acceptance Review Form is included with this report (last page) indicating the draft status of the operations procedure during the OTP. During the OTP 11 test exceptions were encountered. Of these exceptions four were determined to affect Acceptance Criteria as listed in the OTP, Section 4.7 ACCEPTANCE CRITERIA.
Date: September 15, 1997
Creator: Akers, J.C.
Partner: UNT Libraries Government Documents Department