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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

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

Thermionic conversion reactor technology assessment. Final report

Description: The in-core thermionic space nuclear power supply may be the only identified reactor-power concept that can meet the SP-100 size functional requirements with demonstrated state-of-the-art reactor system and space-qualified power system component temperatures. The SP-100 configuration limits provide a net 40 m/sup 2/ of primary non-deployed radiator area. If a reasonable 7-year degradation allowance of 15% to 20% is provided then the beginning of life (BOL) net power output requirement is about 120 kWe. Consequently, the SP-100 power system must produce a P/A of 2.7 kWe/m/sup 2/. This non-deployed radiator area power density performance can only be reasonably achieved by the thermionic in-core convertr system, the potassium Rankine turbine system and the Stirling engine system. The purpose of this study is to examine past and current tests and data, and to assess the potential for successful development of suitable fueled-thermionic converters that will meet SP-100 and growth requirements. The basis for the assessment will be provided and the recommended key developments plan set forth.
Date: February 1, 1984
Partner: UNT Libraries Government Documents Department

Space power technology into the 21st century

Description: This paper discusses the space power systems of the early 21st century. The focus is on those capabilities which are anticipated to evolve from today's state-of-the-art and the technology development programs presently in place or planned for the remainder of the century. The power system technologies considered include solar thermal, nuclear, radioisotope, photovoltaic, thermionic, thermoelectric, and dynamic conversion systems such as the Brayton and Stirling cycles. Energy storage technologies considered include nickel hydrogen biopolar batteries, advanced high energy rechargeable batteries, regenerative fuel cells, and advanced primary batteries. The present state-of-the-art of these space power and energy technologies is discussed along with their projections, trends and goals. A speculative future mission model is postulated which includes manned orbiting space stations, manned lunar bases, unmanned earth orbital and interplanetary spacecraft, manned interplanetary missions, military applications, and earth to space and space to space transportation systems. The various space power/energy system technologies anticipated to be operational by the early 21st century are matched to these missions.
Date: January 1, 1984
Creator: Faymon, K.A. & Fordyce, J.S.
Partner: UNT Libraries Government Documents Department

Nevada Test Site Area 25, Radiological Survey and Cleanup Project, 1974-1983 (a revised final report). Revision 1

Description: This report describes the radiological survey, decontamination and decommissioning (D and D) 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 radiological survey portion of the project encompassed portable instrument surveys and removable contamination surveys (swipe) for beta plus gamma and alpha radioactive 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. 9 references, 23 figures.
Date: December 1, 1984
Creator: Miller, M.G.
Partner: UNT Libraries Government Documents Department

Liquid metal heat transfer issues

Description: An alkali liquid metal cooled nuclear reactor coupled with an alkali metal Rankine cycle provides a practicable option for space systems/missions requiring power in the 1 to 100 MW(e) range. Thermal issues relative to the use of alkali liquid metals for this purpose are identified as these result from the nature of the alkali metal fluid itself, from uncertainties in the available heat transfer correlations, and from design and performance requirements for system components operating in the earth orbital microgravity environment. It is noted that, while these issues require further attention to achieve optimum system performance, none are of such magnitude as to invalidate this particular space power concept.
Date: January 1, 1984
Creator: Hoffman, H.W. & Yoder, G.L.
Partner: UNT Libraries Government Documents Department

Transference of advanced LMFBR control technology to the aerospace power system program

Description: Much recent R and D has been devoted to the safety of liquid metal fast breeder reactors (LMFBR's). Part of the resulting technology, especially advanced control systems, appears to be directly transferable to the space nuclear power program. Some of the ideas described herein have been already culminated in successful products that are available for application, e.g. analytical redundancy and fault-tolerant computers. Others, in various stages of R and D, are being developed as elements to support the design goals outlined in the following section, e.g. automated software verification, automated hardware verification, and system validation.
Date: January 1, 1984
Creator: Chisholm, G.H.
Partner: UNT Libraries Government Documents Department