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Advanced Thermionic Technology Program: summary report. Volume 1. Final report

Description: This report summarizes the progress made by the Advanced Thermionic Technology Program during the past several years. This program, sponsored by the US Department of Energy, has had as its goal adapting thermionic devices to generate electricity in a terrestrial (i.e., combustion) environment. The technology has previously been developed for astronautical applications. The report is organized in four volumes, each focused as much as possible on the needs of a particular audience. Volume 1 contains Part A, the Executive Summary. This Executive Summary describes the accomplishments of the Program in brief, but assumes the reader's familiarity with the thermionic process and the technical issues associated with the Program. For this reason, Volume 1 also contains Part B, a minimally technical overview of the Advanced Thermionic Technology Program. Volume 2 (Part C) concentrates on the progress made in developing and fabricating the ''current generation'' of chemical vapor deposited hot shell thermionic converters and is addressed to those primarily concerned with today's capabilities in terrestrial thermionic technology. Volume 3 (Part D) contains the results of systems studies of primary interest to those involved in identifying and evaluating applications for thermionics. Volume 4 (Part E) is a highly technical discussion of the attempts made by the program to push the state-of-the-art beyond the current generation of converters and is directed toward potential researchers engaged in this same task. These technical discussions are complemented with Appendices where appropriate.
Date: October 1, 1984
Partner: UNT Libraries Government Documents Department

Advanced Thermionic Technology Program: summary report. Volume 4. Final report

Description: This report summarizes the progress made by the Advanced Thermionic Technology Program during the past several years. This Program, sponsored by the US Department of Energy, has had as its goal adapting thermionic devices to generate electricity in a terrestrial (i.e., combustion) environment. Volume 4 (Part E) is a highly technical discussion of the attempts made by the Program to push the state-of-the-art beyond the current generation of converters and is directed toward potential researchers engaged in this same task. These technical discussions are complemented with Appendices where appropriate.
Date: October 1, 1984
Partner: UNT Libraries Government Documents Department

Advanced Thermionic Technology Program: summary report. Volume 3. Final report

Description: This report summarizes the progress made by the Advanced Thermionic Technology Program during the past several years. This Program, sponsored by the US Department of Energy, has had as its goal adapting thermionic devices to generate electricity in a terrestrial (i.e., combustion) environment. Volume 3 (Part D) contains the results of systems studies of primary interest to those involved in identifying and evaluating applications for thermionics. As a general rule of thumb, cogeneration technologies are most attractive to industries when those technologies naturally produce a ration of electrical to thermal output which closely matches the demand within the industrial facilities themselves. Several of the industries which consume the largest amounts of energy have an electrical-to-thermal ratio of about ten percent, as can be seen in Exhibit D-1.1. This closely matches the electrical efficiency of thermionic converters. Thermionic cogeneration has several other unique advantages relative to alternative technologies for cogeneration which should lead to a much broader application of cogeneration in industry. These advantages accrue from the much higher temperatures at which thermionic energy conversion takes place, its suitability for very small as well as large process heaters, and, of course, its production of direct heat rather than process steam. In fact, thermionics can even be coupled to more conventional cogeneration technologies (e.g., steam turbines) to extend their applicability to processes requiring a greater electrical-to-thermal ratio than either cogeneration technology alone can provide. Several examples of thermionic cogeneration are presented in greater detail: copper refining by the Noranda process; thermionic topping cycles for gas turbine; and combined cycle and fossil-fuel steam power plants. 13 refs., 71 figs.
Date: October 1, 1984
Partner: UNT Libraries Government Documents Department

Development of a high-heat-flux target for multimegawatt, multisecond neutral beams at ORNL

Description: A high-heat-flux target has been developed for intercepting multimegawatt, multisecond neutral beam power at the Oak Ridge National Laboratory (ORNL). Water-cooled copper swirl tubes are used for the heat transfer medium; these tubes exhibit an enhancement in burnout heat flux over conventional axial-flow tubes. The target consists of 126 swirl tubes (each 0.95 cm in outside diameter with 0.16-cm-thick walls and approx. =1 m long) arranged in a V-shape. Two arrays of parallel tubes inclined at an angle ..cap alpha.. to the beam axis form the V-shape, and this geometry reduces the surface heat flux by a factor of 1/sin ..cap alpha.. (for the present design, ..cap alpha.. =13/sup 0/ and 21/sup 0/). In tests with the ORNL long-pulse ion source (13- by 43-cm grid), the target has handled up to 3-MW, 30-s beam pulses with no deleterious effects. The peak power density was estimated at approx. =15 kW/cm/sup 2/ normal to the beam axis (5.4 kW/cm/sup 2/ maximum on tube surfaces). The water flow rate through the target was 41.6 L/s (660 gpm) or 0.33 L/s (5.2 gpm) per tube (axial flow velocity = 11.6 m/s). The corresponding pressure drop across the target was 1.14 MPa (165 psi) with an inlet pressure of 1.45 MPa (210 psia). Data are also presented from backup experiments in which individual tubes were heated by a small ion source (10-cm-diam grid) to characterize tube performance. These results suggest that the target should handle peak power densities in the range 25 to 30 kW/cm/sup 2/ normal to the beam axis (approx. =10 kW/cm/sup 2/ maximum on tube surfaces) with the present flow parameters. This translates to beam power levels of 5 to 6 MW for equivalent beam optics.
Date: January 1, 1984
Creator: Combs, S.K.; Milora, S.L.; Bush, C.E.; Foster, C.A.; Haselton, H.H.; Hayes, P.H. et al.
Partner: UNT Libraries Government Documents Department

Advanced Thermionic Technology Program: summary report. Volume 2. Final report

Description: This report summarizes the progress made by the Advanced Thermionic Technology Program during the past several years. This Program, sponsored by the US Department of Energy, has had as its goal adapting thermionic devices to generate electricity in a terrestrial (i.e., combustion) environment. The technology has previously been developed for astronautical applications. Volume 2 (Part C) concentrates on the progress made in developing and fabricating the ''current generation'' of chemical vapor deposited hot shell thermionic converters and is addressed to those primarily concerned with today's capabilities in terrestrial thermionic technology. 30 refs., 83 figs.
Date: October 1, 1984
Partner: UNT Libraries Government Documents Department

Forming of metal components for radioisotope heat sources

Description: Flight-quality iridium components can be fabricated from iridium alloys by modifying standard production processes. A large quantity of metrological and NDE data support the quality of these devices, which, in turn, justify their use in containing plutonium fuel for space system applications.
Date: January 1, 1984
Creator: Johnson, E.W.
Partner: UNT Libraries Government Documents Department

SP-100 thermionic technology program annual integrated technical progress report for the period ending September 30, 1984

Description: The thermionic technology program addresses the feasibility issues of a seven-year-life thermionic fuel element (TFE) for the SP-100 Thermionic Reactor Space Power System. These issues relate to the extension of TFE lifetime from three to seven years, one of the SP-100 requirements. The technology to support three-year lifetimes was demonstrated in the earlier TFE development program conducted in the late-1960s and 1970s. Primary life-limiting factors were recognized to be thermionic emitter dimensional increases due to swelling of the nuclear fuel and electrical structural damage from fast neutrons. The 1984-85 technology program is investigating the fueled emitter and insulator lifetime issues, both experimentally and analytically. The goal is to analytically project the lifetime of the fueled emitter and insulator and to experimentally verify these projection methods. In 1984, the efforts were largely devoted to the design and building of fueled emitters for irradiation in 1985, validation of fuel-emitter models, development of irradiation-resistant metal-ceramic seal and sheath insulator, modeling of insulator lifetime, and development of wide-spread, high-performance thermionic converters.
Date: November 1, 1984
Creator: Holland, J.W. (ed.)
Partner: UNT Libraries Government Documents Department

Nevada Test Site Area 25. Radiological survey and cleanup project, 1974-1983. Final report

Description: This report describes radiological survey, decontamination and decommissioning of the Nevada Test Site (NTS) Area 25 facilities and land areas incorporated in the Nuclear Rocket Development Station (NRDS). Buildings, facilities and support systems used after 1959 for nuclear reactor and engine testing were surveyed for the presence of radioactive contamination. The cleanup was part of the Surplus Facilities Management Program funded by the Department of Energy's Richland Operations Office. The radiological survey portion of the project encompassed portable instrument surveys and removable contamination surveys (swipe) for alpha and beta plus gamma radiation contamination of facilities, equipment and land areas. Soil sampling was also accomplished. The majority of Area 25 facilities and land areas have been returned to unrestricted use. Remaining radiologically contaminated areas are posted with warning signs and barricades. 12 figures.
Date: January 1, 1984
Creator: McKnight, R.K.; Rosenberry, C.E. & Orcutt, J.A.
Partner: UNT Libraries Government Documents Department

Reducing hot-short cracking in iridium GTA welding using four-pole oscillation

Description: Hot-short cracking, an intrinsic problem in iridium welding, has been reduced using four-pole magnetic arc oscillation. For given batches of iridium, reject rates have been reduced from 26% to 2%. The mechanics of the four-pole oscillator, the microstructural effects and the causes for improvement are discussed.
Date: January 1, 1984
Creator: Scarbrough, J.D. & Burgan, C.E.
Partner: UNT Libraries Government Documents Department

Ir/PuO/sub 2/ compatibility: transfer of impurities from plutonium dioxide to iridium metal during high temperature aging

Description: Plutonium oxide fuel pellets for powering radioisotopic thermoelectric generators for NASA space vehicles are encapsulated in iridium which has been grain-boundary-stabilized with thorium and aluminum. After aging for 6 months at 1310/sup 0/C under vacuum, enhanced grain growth is observed in the near-surface grains of the iridium next to the PuO/sub 2/. Examination of the grain boundaries by AES and SIMS shows a depletion of thorium and aluminum. Iron, chromium, and nickel from the fuel were found to diffuse into the iridium along the grain boundaries. Enhanced grain growth appears to result from thorium depletion in the grain boundaries of the near-surface grains next to the fuel. However, in one instance grain growth was slowed by the formation of thorium oxide by oxygen diffusing up the grain boundaries.
Date: January 1, 1984
Creator: Taylor, D. H.; Christie, W. H. & Pavone, D.
Partner: UNT Libraries Government Documents Department

Space nuclear safety program. Progress report, January 1984

Description: This technical monthly report covers studies related to the use of /sup 238/PuO/sub 2/ in radioisotope power systems carried out for the Office of Special Nuclear Projects of the US Department of Energy by Los Alamos National Laboratory. Most of the studies discussed here are ongoing. Results and conclusions described may change as the work continues.
Date: July 1, 1984
Creator: Bronisz, S.E. (comp.)
Partner: UNT Libraries Government Documents Department

Space Nuclear Space Program. Progress report, December 1983

Description: This technical monthly report covers studies related to the use of /sup 238/PuO/sub 2/ in radioisotope power systems carried out for the Office of Special Nuclear Projects of the US Department of Energy by Los Alamos National Laboratory. Results from safety-verification tests including impact tests are presented.
Date: June 1, 1984
Creator: Bronisz, S.E. (comp.)
Partner: UNT Libraries Government Documents Department

Long-term exposure of pressed plutonium oxide heat sources to aquatic environments

Description: Plutonium-238 oxide fuel pellets were exposed to water for 2.5 to 6.4 yr, and the concentration of plutonium in the water was monitored. Water composition and temperature were found to be important factors in determining the rate of plutonium release into the water. Typical release rates ranged from 10 to 40 ng/m/sup 2//s in cold fresh water and from 0.3 to 11 ng/m/sup 2//s in cold sea water. Release rates in sea water varied over time and sometimes were erratic. The plutonium release per unit area did not depend on the size of the PuO/sub 2/ source. The released plutonium was in an extremely fine form, able to pass through 10,000 molecular weight cutoff filters. Apparent differences in the fuel pellet surfaces after exposure suggest that plutonium release is controlled by physical and chemical processes occurring at the solid-liquid interface. Release mechanisms and their implications are discussed.
Date: November 1, 1984
Creator: Heaton, R.C.; Patterson, J.H.; Kosiewicz, S.T.; Matlack, G.M.; Steinkruger, F.J.; Nelson, G.B. et al.
Partner: UNT Libraries Government Documents Department

Controlled PuO/sub 2/ particle size from Pu(III) oxalate precipitation

Description: PuO/sub 2/ with reproducible particle size and morphology can be produced by controlling precipitation variables affecting the initial supersaturation and final solubility of plutonium oxalate. Such feed powders with constant characteristics are essential for reproducible fabrication response and controlled microstructures in the manufacture of /sup 238/PuO/sub 2/ heat sources. Calcination does not change the morphology or shape of the size distribution of the PuO/sub 2/ particles from that of the precipitated Pu(III) hydrated oxalate. For a given precipitation method, the size and morphology of the Pu(III) oxalate are determined by precipitation temperature, nitric acid concentration, plutonium concentration, and oxalate ion concentration. Functional relationships of these variables were developed to control and predetermine the size, extent of agglomeration, and dimensions of the PuO/sub 2/ particles over the range of these variables for PuO/sub 2/ production. This report describes statistically designed factorial experiments and characterization of PuO/sub 2/ by Coulter counter and scanning electron microscopy (SEM). These control factors were applied successfully in full-scale production.
Date: October 1, 1984
Creator: Burney, G.A. & Smith, P.K.
Partner: UNT Libraries Government Documents Department

Reliability analysis using network simulation

Description: A computer code that uses a dynamic, Monte Carlo modeling approach is Q-GERT (Graphical Evaluation and Review Technique--with Queueing), and the present study has demonstrated the feasibility of using Q-GERT for modeling time-dependent, unconditionally and conditionally linked phenomena that are characterized by arbitrarily selected probability distributions.
Date: January 1, 1984
Partner: UNT Libraries Government Documents Department

Space nuclear safety program. Progress report, August 1983

Description: This technical monthly report covers studies related to the use of /sup 238/PuO/sub 2/ in radioisotope power systems carried out for the Office of Special Nuclear Projects of the US Department of Energy by Los Alamos National Laboratory. Most of the studies discussed here are ongoing. Results and conclusions described may change as the work continues.
Date: January 1, 1984
Creator: Bronisz, S.E. (comp.)
Partner: UNT Libraries Government Documents Department

Space Nuclear Safety Program. Progress report

Description: This technical monthly report covers studies related to the use of /sup 238/PuO/sub 2/ in radioisotope power systems carried out for the Office of Special Nuclear Projects of the US Department of Energy by Los Alamos National Laboratory. Most of the studies discussed here are ongoing. Results and conclusions described may change as the work continues.
Date: January 1, 1984
Creator: Bronisz, S.E. (comp.)
Partner: UNT Libraries Government Documents Department

Space reactor fuels performance and development issues. [SP-100; 100 kW(e)]

Description: Three compact reactor concepts are now under consideration by the US Space Nuclear Power Program (the SP-100 Program) as candidates for the first 100-kWe-class space reactor. Each of these reactor designs puts unique constraints and requirements on the fuels system, and raises issues of fuel systems feasibility and performance. This paper presents a brief overview of the fuel requirements for the proposed space reactor designs, a delineation of the technical feasibility issues that each raises, and a description of the fuel systems development and testing program that has been established to address key technical issues.
Date: January 1, 1984
Creator: Wewerka, E.M.
Partner: UNT Libraries Government Documents Department

Overview of NASA Lewis Research Center free-piston Stirling engine activities

Description: An overview of the National Aeronautics and Space Administration (NASA) Lewis Research Center (LeRC) free-piston Stirling engine activities is presented. These include (1) a generic free-piston Stirling technology project being conducted to develop technologies generic to both space power and terrestrial heat pump applications in a cooperative, cost-shared effort with the Department of Energy (DOE)/Oak Ridge National Laboratory (ORNL); and (2) a free-piston Stirling space power technology feasibility demonstration project being conducted in support of the Defense Advanced Research Projects Agency (DARPA), DOE, NASA, SP-100 project. The generic technology effort includes extensive parametric testing of a 1 kW free-piston Stirling engine (RE-1000), development of a free-piston Stirling performance computer code, design and fabrication under contract of a hydraulic output modification for RE-1000 engine tests, and a 1000-hour endurance test, under contract, of a 3 kWe free-piston Stirling/alternator engine. The newly initiated space power technology feasibility demonstration effort addresses the capability of scaling a free-piston Stirling/alternator system to about 25 kWe; developing thermodynamic cycle efficiency greater than or equal to 70 percent of Carnot at temperature ratios in the order of 1.5 to 2.0; achieving a power conversion unit specific weight of 6 kg/kWe; operating with noncontacting gas bearings; and dynamically balancing the system. Planned engine and component design and test efforts are described.
Date: January 1, 1984
Creator: Slaby, J.G.
Partner: UNT Libraries Government Documents Department

Space nuclear power system and the design of the nuclear electric propulsion OTV

Description: Payload increases of three to five times that of the Shuttle/Centaur can be achieved using nuclear electric propulsion. Various nuclear power plant options being pursued by the SP-100 Program are described. These concepts can grow from 100 kW/sub e/ to 1MW/sub e/ output. Spacecraft design aspects are addressed, including thermal interactions, plume interactions, and radiation fluences. A baseline configuration is described accounting for these issues. Safety aspects of starting the OTV transfer from an altitude of 300 km indicate no significant additional risk to the biosphere.
Date: January 1, 1984
Creator: Buden, D. & Garrison, P.W.
Partner: UNT Libraries Government Documents Department

Space reactors: What is a kilogram

Description: The use of nuclear electric propulsion can triple payloads to GEO for a single Shuttle launch. Life orbits of 300 years can be used to allow most of the fission and activation products to decay before a reactor reenters the biosphere. Enough radioactive materials remain with very long lifetimes to make it desirable to design the reactor to disperse upon reentry and little additional risk to the biosphere is introduced by initiating NEP operations from 300 km.
Date: January 1, 1984
Creator: Buden, D.; Angelo, J. Jr.; Ek, D. & Voss, S.
Partner: UNT Libraries Government Documents Department