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Fundamental studies of fusion plasmas. Final report

Description: Lodestar has carried out a vigorous research program in the areas of rf, edge plasma and divertor physics, with emphasis largely geared towards improving the understanding and performance of ion-cyclotron heating and current drive (ICRF) systems. Additionally, a research program in the field of edge plasma and divertor modeling was initiated. Theoretical work on high power rf sheath formation for multi-strap rf arrays was developed and benchmarked against recent experimental data from the new JET A2 antennas. Sophisticated modeling tools were employed to understand the sheath formation taking into account realistic three-dimensional antenna geometry. A novel physics explanation of an observed anomaly in the low power loading of antennas was applied to qualitatively interpret data on DIII-D in terms of rf sheaths, and potential applications of the idea to develop a near-field sheath diagnostic were explored. Other rf-wave related topics were also investigated. Full wave ICRF modeling studies were carried out in support of ongoing and planned tokamaks experiments, including the investigation of low frequency plasma heating and current drive regimes for IGNITOR. In a cross-disciplinary study involving both MHD and ICRF physics, ponderomotive feedback stabilization by rf was investigated as a potential means of controlling external kink mode disruptions. In another study, the instability of the ion hybrid wave (IHW) in the presence of fusion alpha particles was studied. In the field of edge plasma and divertor modeling studies, Lodestar began the development of a theory of generalized ballooning and sheath instabilities in the scrape off layer (SOL) of divertor tokamaks. A detailed summary of the technical progress in these areas during the contract period is included, as well as where references to published work can be found. A separate listing of publications, meeting abstracts, and other presentations is also given at the end of this final report.
Date: January 30, 1998
Creator: Aamodt, R.E.
Partner: UNT Libraries Government Documents Department

Hanford Nuclear Energy Center: a conceptual study

Description: The objective of the study is to develop an improved understanding of the nuclear energy center (NEC) concept and to identify research and development needed to evaluate the concept fully. A specific context was selected for the study--the Hanford site. Thus, the study primarily addresses the HNEC concept, but the findings are extrapolated to generic NECs where possible. The major emphasis in the HNEC study was to explore potential technical and environmental problems in a specific context and in sufficient detail to evaluate potential problems and propose practical solutions. The areas of concern are typical of those considered in preparing environmental and safety analysis reports, including: topics dealing with engineering choices (e.g., site selection, heat sink management, electrical transmission, and reliability of generation); environmental matters (e.g., terrestrial and radiological effects); socioeconomic factors (e.g., community impacts); and licensing considerations.
Date: September 30, 1978
Creator: Harty, H. (comp.)
Partner: UNT Libraries Government Documents Department

Standardized Testing Program for Solid-State Hydrogen Storage Technologies

Description: In the US and abroad, major research and development initiatives toward establishing a hydrogen-based transportation infrastructure have been undertaken, encompassing key technological challenges in hydrogen production and delivery, fuel cells, and hydrogen storage. However, the principal obstacle to the implementation of a safe, low-pressure hydrogen fueling system for fuel-cell powered vehicles remains storage under conditions of near-ambient temperature and moderate pressure. The choices for viable hydrogen storage systems at the present time are limited to compressed gas storage tanks, cryogenic liquid hydrogen storage tanks, chemical hydrogen storage, and hydrogen absorbed or adsorbed in a solid-state material (a.k.a. solid-state storage). Solid-state hydrogen storage may offer overriding benefits in terms of storage capacity, kinetics and, most importantly, safety.The fervor among the research community to develop novel storage materials had, in many instances, the unfortunate consequence of making erroneous, if not wild, claims on the reported storage capacities achievable in such materials, to the extent that the potential viability of emerging materials was difficult to assess. This problem led to a widespread need to establish a capability to accurately and independently assess the storage behavior of a wide array of different classes of solid-state storage materials, employing qualified methods, thus allowing development efforts to focus on those materials that showed the most promise. However, standard guidelines, dedicated facilities, or certification programs specifically aimed at testing and assessing the performance, safety, and life cycle of these emergent materials had not been established. To address the stated need, the Testing Laboratory for Solid-State Hydrogen Storage Technologies was commissioned as a national-level focal point for evaluating new materials emerging from the designated Materials Centers of Excellence (MCoE) according to established and qualified standards. Working with industry, academia, and the U.S. government, SwRI set out to develop an accepted set of evaluation standards and analytical methodologies. Critical ...
Date: July 30, 2012
Creator: Miller, Michael A. & Page, Richard A.
Partner: UNT Libraries Government Documents Department

Spent Fuel Test-Climax: An evaluation of the technical feasibility of geologic storage of spent nuclear fuel in granite: Final report

Description: In the Climax stock granite on the Nevada Test Site, eleven canisters of spent nuclear reactor fuel were emplaced, and six electrical simulators were energized. When test data indicated that the test objectives were met during the 3-year storage phase, the spent-fuel canisters were retrieved and the thermal sources were de-energized. The project demonstrated the feasibility of packaging, transporting, storing, and retrieving highly radioactive fuel assemblies in a safe and reliable manner. In addition to emplacement and retrieval operations, three exchanges of spent-fuel assemblies between the SFT-C and a surface storage facility, conducted during the storage phase, furthered this demonstration. The test led to development of a technical measurements program. To meet these objectives, nearly 1000 instruments and a computer-based data acquisition system were deployed. Geotechnical, seismological, and test status data were recorded on a continuing basis for the three-year storage phase and six-month monitored cool-down of the test. This report summarizes the engineering and scientific endeavors which led to successful design and execution of the test. The design, fabrication, and construction of all facilities and handling systems are discussed, in the context of test objectives and a safety assessment. The discussion progresses from site characterization and experiment design through data acquisition and analysis of test data in the context of design calculations. 117 refs., 52 figs., 81 tabs.
Date: March 30, 1986
Creator: Patrick, W.C. (comp.)
Partner: UNT Libraries Government Documents Department

Data Catalog for Models Simulating Release of Contaminants from Hanford Site Waste Sources

Description: This report is an update to the previously published catalog that summarized information published since 1987 on models that have been used to simulate release of chemical and radioactive contaminants from waste sources on the Hanford Site. Tables in this report provide links to data sources needed to implement release models. These links enable users to quickly locate the specific release model information and data they need to apply the models to future site assessments.
Date: August 30, 2003
Creator: Riley, Robert G. & Lopresti, Charles A.
Partner: UNT Libraries Government Documents Department

World Trade Organization: Standard of Review and Impact of Trade Remedy Rulings

Description: A letter report issued by the General Accounting Office with an abstract that begins "World Trade Organization (WTO) members rely on trade remedies in the form of duties or other import restrictions to protect their industries from injury due to unfair foreign trade practices or unexpected import surges. There is congressional concern that the WTO, created in 1995 to administer trade rules, is interfering with this ability. There is also congressional concern that the WTO is not treating the United States fairly in resolving trade remedy disputes. A congressional requester asked GAO to identify trends in WTO trade remedy disputes since 1995, including the outcomes of these disputes and how they affected members' ability to impose trade remedies. The requester also asked GAO to discuss the standards of review that the WTO applies when ruling on trade remedy disputes and to present U.S. agencies' and legal experts' views on the WTO's application of these standards and related trade remedy issues. In their comments on a draft of this report, the Department of Commerce and the U.S. International Trade Commission stated that the report needed to put more emphasis on U.S. agencies' concerns about the potential adverse impact of WTO rulings on the U.S.'s use of trade remedies. The U.S. Trade Representative provided only technical comments on the report. GAO modified the report as appropriate."
Date: July 30, 2003
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department


Description: This document lists experimental references added to Nuclear Science References (NSR) during the period April 1, 2005 to June 30, 2005. The first section lists keynumbers and keywords sorted by mass and nuclide. The second section lists all references, ordered by keynumber.
Date: June 30, 2005
Creator: WINCHELL, D.F.
Partner: UNT Libraries Government Documents Department

ICRF antenna modeling and simulation. Final report, March 1, 1993--May 31, 1996

Description: SAIC has undergone a three year research and development program in support of the DOE Office of Fusion Energy`s (OFE) program in Ion Cyclotron Range of Frequencies (ICRF) heating of present, next generation, and future plasma fusion devices. The effort entailed advancing theoretical models and numerical simulation technology of ICRF physics and engineering issues associated predominately with, but not limited to, tokamak Ion Cyclotron Heating (ICH) and fast wave current drive (FWCD). Ion cyclotron heating and current drive is a central element in all current and planned large fusion experiments. In recent years, the variety of uses for ICRF systems has expanded, and includes the following: (1) Heating sufficient to drive plasma to ignition. (a) Second-harmonic T heating. (b) He{sup 3} minority heating. (2) Second-harmonic He{sup 4} heating in H plasma (for non-activated phase). (3) Detailed equilibrium profile control minority heating. (a) Ion minority (He{sup 3}) CD (for profile control on inside of plasma). (b) Ion minority (He{sup 3}) CD (for profile control on outside of plasma). (4) Ion-ion hybrid regime majority ion heating. (5) Electron current drive. (6) Mode conversion to drive current. (7) Deuterium minority heating. (8) Sawtooth instability stabilization. (9) Alpha particle parameter enhancement. (10) The generation of minority tails by ICRF to simulate D-T plasma particle physics in a deuterium plasma. Optimization of ICRF antenna performance for either heating or current drive depends critically on the complex balance and interplay between the plasma physics and the electromechanical system requirements. For example, ITER IC rf designs call for an IC. system frequency range from 20 MHz to 100 MHz. Additionally, antenna designs and operational modes that minimize impurity production and induced sheath formation may degrade current drive efficiency. Such effects have been observed in experiments involving it versus zero antenna phasing.
Date: August 30, 1996
Partner: UNT Libraries Government Documents Department