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Microwave Diagnostics for High-Temperature Plasmas

Description: This report presents the high-temperature plasma research, aimed mainly toward controlled thermonuclear reactions, that have been greatly facilitated by the development of a number of microwave diagnostics, based on previous plasma microwave studies but mostly on ideas generated at UCRL in conjunction with the AEC Project Sherwood.
Date: March 1957
Creator: Wharton, Charles B.
Partner: UNT Libraries Government Documents Department

System Evaluation and Life-Cycle Cost Analysis of a Commercial-Scale High-Temperature Electrolysis Hydrogen Production Plant

Description: Results of a system evaluation and lifecycle cost analysis are presented for a commercial-scale high-temperature electrolysis (HTE) central hydrogen production plant. The plant design relies on grid electricity to power the electrolysis process and system components, and industrial natural gas to provide process heat. The HYSYS process analysis software was used to evaluate the reference central plant design capable of producing 50,000 kg/day of hydrogen. The HYSYS software performs mass and energy balances across all components to allow optimization of the design using a detailed process flow sheet and realistic operating conditions specified by the analyst. The lifecycle cost analysis was performed using the H2A analysis methodology developed by the Department of Energy (DOE) Hydrogen Program. This methodology utilizes Microsoft Excel spreadsheet analysis tools that require detailed plant performance information (obtained from HYSYS), along with financial and cost information to calculate lifecycle costs. The results of the lifecycle analyses indicate that for a 10% internal rate of return, a large central commercial-scale hydrogen production plant can produce 50,000 kg/day of hydrogen at an average cost of $2.68/kg. When the cost of carbon sequestration is taken into account, the average cost of hydrogen production increases by $0.40/kg to $3.08/kg.
Date: November 1, 2012
Creator: Harvego, Edwin A.; O'Brien, James E. & McKellar, Michael G.
Partner: UNT Libraries Government Documents Department

Application of Spatially Resolved High Resolution Crystal Spectrometry to ICF Plasmas

Description: High resolution (λ/Δ#3;λ ~ 10 000) 1D imaging x-ray spectroscopy using a spherically bent crystal and a 2D hybrid pixel array detector is used world wide for Doppler measurements of ion-temperature and plasma flow-velocity profiles in magnetic confinement fusion plasmas. Meter sized plasmas are diagnosed with cm spatial resolution and 10 ms time resolution. This concept can also be used as a diagnostic of small sources, such as inertial confinement fusion plasmas and targets on x-ray light source beam lines, with spatial resolution of micrometers, as demonstrated by laboratory experiments using a 250-μm 55 Fe source, and by ray-tracing calculations. Throughput calculations agree with measurements, and predict detector counts in the range 10-8 -10-6 times source x-rays, depending on crystal reflectivity and spectrometer geometry. Results of the lab demonstrations, application of the technique to the National Ignition Facility (NIF), and predictions of performance on NIF will be presented.
Date: September 15, 2012
Creator: Hill, Kenneth W.; Bitter, M.; Delgado-Aprico, L.; Pablant, N. A.; Beirersdorfer, P.; Schneider, M. et al.
Partner: UNT Libraries Government Documents Department

Presentation on facility problems in high-temperature structures research

Description: Presentation regarding the current general approach of NACA to the problems of high-temperature structures research facilities. The field is rapidly changing and many investigations discussed are still in the exploratory stage. The main areas of importance are heating, loading, and structural model accommodation as well as having the proper research equipment and heat exchangers.
Date: March 27, 1956
Creator: Purser, Paul E. & Heldenfels, Richard R.
Partner: UNT Libraries Government Documents Department

Transient Temperature Variations During the Self-Heating of a Plasma by Thermonuclear Reactions

Description: Abstract: "The possibility of transient temperature variations during the self-heating of a plasma by thermonuclear reactions was investigated. Calculations were performed on an IBM Card Program Calculator. Estimates of the time scale for self-heating were obtained. It was concluded that it would be unsafe to assume that the nuclear temperature is always equal to or greater than the electron temperature in a discussion of plasma instabilities for a plasma with 10 percent or greater tritium concentration."
Date: March 21, 1955
Creator: Greyber, Howard D.
Partner: UNT Libraries Government Documents Department

A Study of the Impact Behavior of High-Temperature Materials

Description: Note presenting the impact properties of titanium carbide base cermets, some high-temperature alloys, and the intermetallic NiAl, obtained at room and elevated temperatures up to 1750 degrees Fahrenheit. The impact energies of cermets were found to increase with increased amounts of metallic binder. Results regarding the variables of drop test, impact resistance of cermets, high-temperature alloys, and comparison of cermets and alloys are provided.
Date: March 1957
Creator: Probst, H. B. & McHenry, Howard T.
Partner: UNT Libraries Government Documents Department

Tensile Fracturing Characteristics of Several High-Temperature Alloys as Influenced by Orientation in Respect to Forging Direction

Description: Memorandum presenting the effects of specimen-axis orientation with respect to forging direction on the true stress-strain curves and the fracturing characteristics at room temperature of forged and subsequently heat-treated billets of alloys 16-25-6, S-816, and Inconel X. Results regarding plastic properties and fracture properties are provided.
Date: February 12, 1951
Creator: Brown, W. F., Jr.; Schwartzbart, H. & Jones, M. H.
Partner: UNT Libraries Government Documents Department

High-Temperature Superconductivity in Perspective

Description: This is the second of two OTA assessments on the subject of high-temperature superconductivity (HTS). As the title suggests, this study attempts to put HTS in perspective, both in terms of competing technologies (e.g., the more mature low-temperature superconductors), and in terms of the many technical and economic problems that must be overcome before HTS can be widely used.
Date: April 1990
Creator: United States. Congress. Office of Technology Assessment.
Partner: UNT Libraries Government Documents Department

Commercializing high-temperature superconductivity

Description: Since the discovery of high-temperature superconductivity (HTS), research laboratories around the world have pushed the temperature limits steadily upward, opening the way to commercial applications with potentially revolutionary impacts. The scientific race is becoming a commercial race, one featuring U.S. and Japanese companies, and one that the United States could lose. Indeed, American firms may already be falling behind in commercializing the technology of superconductivity.
Date: June 1988
Creator: United States. Congress. Office of Technology Assessment.
Partner: UNT Libraries Government Documents Department

Safeguards-by-Design: Guidance for High Temperature Gas Reactors (HTGRs) With Pebble Fuel

Description: The following is a guidance document from a series prepared for the U.S. Department of Energy (DOE) National Nuclear Security Administration (NNSA), under the Next Generation Safeguards Initiative (NGSI), to assist facility designers and operators in implementing international Safeguards-by-Design (SBD). SBD has two main objectives: (1) to avoid costly and time consuming redesign work or retrofits of new nuclear fuel cycle facilities and (2) to make the implementation of international safeguards more effective and efficient at such facilities. In the long term, the attainment of these goals would save industry and the International Atomic Energy Agency (IAEA) time, money, and resources and be mutually beneficial. This particular safeguards guidance document focuses on pebble fuel high temperature gas reactors (HTGR). The purpose of the IAEA safeguards system is to provide credible assurance to the international community that nuclear material and other specified items are not diverted from peaceful nuclear uses. The safeguards system consists of the IAEA’s statutory authority to establish safeguards; safeguards rights and obligations in safeguards agreements and additional protocols; and technical measures implemented pursuant to those agreements. Of foremost importance is the international safeguards agreement between the country and the IAEA, concluded pursuant to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). According to a 1992 IAEA Board of Governors decision, countries must: notify the IAEA of a decision to construct a new nuclear facility as soon as such decision is taken; provide design information on such facilities as the designs develop; and provide detailed design information based on construction plans at least 180 days prior to the start of construction, and on "as-built" designs at least 180 days before the first receipt of nuclear material. Ultimately, the design information will be captured in an IAEA Design Information Questionnaire (DIQ), prepared by the facility operator, typically with ...
Date: August 1, 2012
Creator: Durst, Philip Casey & Schanfein, Mark
Partner: UNT Libraries Government Documents Department

Advanced High-Temperature Reactor Dynamic System Model Development: April 2012 Status

Description: The Advanced High-Temperature Reactor (AHTR) is a large-output fluoride-salt-cooled high-temperature reactor (FHR). An early-phase preconceptual design of a 1500 MW(e) power plant was developed in 2011 [Refs. 1 and 2]. An updated version of this plant is shown as Fig. 1. FHRs feature low-pressure liquid fluoride salt cooling, coated-particle fuel, a high-temperature power cycle, and fully passive decay heat rejection. The AHTR is designed to be a “walk away” reactor that requires no action to prevent large off-site releases following even severe reactor accidents. This report describes the development of dynamic system models used to further the AHTR design toward that goal. These models predict system response during warmup, startup, normal operation, and limited off-normal operating conditions. Severe accidents that include a loss-of-fluid inventory are not currently modeled. The scope of the models is limited to the plant power system, including the reactor, the primary and intermediate heat transport systems, the power conversion system, and safety-related or auxiliary heat removal systems. The primary coolant system, the intermediate heat transport system and the reactor building structure surrounding them are shown in Fig. 2. These systems are modeled in the most detail because the passive interaction of the primary system with the surrounding structure and heat removal systems, and ultimately the environment, protects the reactor fuel and the vessel from damage during severe reactor transients. The reactor silo also plays an important role during system warmup. The dynamic system modeling tools predict system performance and response. The goal is to accurately predict temperatures and pressures within the primary, intermediate, and power conversion systems and to study the impacts of design changes on those responses. The models are design tools and are not intended to be used in reactor qualification. The important details to capture in the primary system relate to flows within ...
Date: April 30, 2012
Creator: Qualls, A.L.; Cetiner, M.S. & Wilson, T.L., Jr.
Partner: UNT Libraries Government Documents Department

Thermal Expansion of Rare Earth Metals

Description: High temperature dilatometric investigation of the rare earth metals undertaken as part of a broad program of study of these elements, the ultimate goal being better understanding of metals in general.
Date: June 1956
Creator: Barson, Fred; Legvold, S. & Spedding, F. H.
Partner: UNT Libraries Government Documents Department

Kinetic and Thermochemical Studies of the Recombination Reaction Na + O₂ + N₂ from 590 to 1515 K by a Modified High-Temperature Photochemistry Technique

Description: Article on kinetic and thermochemical studies of the recombination reaction sodium + oxygen + nitrogen from 590 to 1515 K by a modified high-temperature photochemistry technique.
Date: September 1, 1989
Creator: Marshall, Paul & Narayan, A. S.
Partner: UNT College of Arts and Sciences

A review of the thermodynamic, transport, and chemical reaction rate properties of high-temperature air

Description: Thermodynamic and transport properties of high temperature air, and the reaction rates for the important chemical processes which occur in air, are reviewed. Semiempirical, analytic expressions are presented for thermodynamic and transport properties of air. Examples are given illustrating the use of these properties to evaluate (1) equilibrium conditions following shock waves, (2) stagnation region heat flux to a blunt high-speed body, and (3) some chemical relaxation lengths in stagnation region flow.
Date: July 1958
Creator: Hansen, C. Frederick & Heims, Steve P.
Partner: UNT Libraries Government Documents Department

Tritium Formation and Mitigation in High-Temperature Reactor Systems

Description: Tritium is a radiologically active isotope of hydrogen. It is formed in nuclear reactors by neutron absorption and ternary fission events and can subsequently escape into the environment. To prevent the tritium contamination of proposed reactor buildings and surrounding sites, this study examines the root causes and potential mitigation strategies for permeation of tritium (such as: materials selection, inert gas sparging, etc...). A model is presented that can be used to predict permeation rates of hydrogen through metallic alloys at temperatures from 450–750 degrees C. Results of the diffusion model are presented for a steady production of tritium
Date: March 1, 2013
Creator: Sabharwall, Piyush; Stoots, Carl & Schmutz, Hans A.
Partner: UNT Libraries Government Documents Department

Tritium Formation and Mitigation in High-Temperature Reactors

Description: Tritium is a radiologically active isotope of hydrogen. It is formed in nuclear reactors by neutron absorption and ternary fission events and can subsequently escape into the environment. To prevent the tritium contamination of proposed reactor buildings and surrounding sites, this study examines the root causes and potential mitigation strategies for permeation of tritium (such as: materials selection, inert gas sparging, etc...). A model is presented that can be used to predict permeation rates of hydrogen through metallic alloys at temperatures from 450–750 degrees C. Results of the diffusion model are presented for a steady production of tritium
Date: October 1, 2012
Creator: Sabharwall, Piyush & Stoots, Carl
Partner: UNT Libraries Government Documents Department

Tritium Formation and Mitigation in High Temperature Reactors

Description: Tritium is a radiologically active isotope of hydrogen. It is formed in nuclear reactors by neutron absorption and ternary fission events and can subsequently escape into the environment. In order to prevent the tritium contamination of proposed reactor buildings and surrounding sites, this paper examines the root causes and potential solutions for the production of this radionuclide, including materials selection and inert gas sparging. A model is presented that can be used to predict permeation rates of hydrogen through metallic alloys at temperatures from 450–750°C. Results of the diffusion model are presented for one steadystate value of tritium production in the reactor.
Date: August 1, 2012
Creator: Sabharwall, Piyush & Stoots, Carl
Partner: UNT Libraries Government Documents Department

Challenges in the Development of Advanced Reactors

Description: Past generations of nuclear reactors have been successively developed and the next generation is currently being developed, demonstrating the constant progress and technical and industrial vitality of nuclear energy. In 2000 US Department of Energy launched Generation IV International Forum (GIF) which is one of the main international frameworks for the development of future nuclear systems. The six systems that were selected were: sodium cooled fast reactor, lead cooled fast reactor, supercritical water cooled reactor, very high temperature gas cooled reactor (VHTR), gas cooled fast reactor and molten salt reactor. This paper discusses some of the proposed advanced reactor concepts that are currently being researched to varying degrees in the United States, and highlights some of the major challenges these concepts must overcome to establish their feasibility and to satisfy licensing requirements.
Date: August 1, 2012
Creator: Sabharwall, P.; Teague, M.C.; Bragg-Sitton, S.M. & Patterson, M.W.
Partner: UNT Libraries Government Documents Department