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ANALYSIS OF SNAP REACTOR COOLANT CROSS-FLOW IN THE SNAP-2 REACTOR EXCLUDING THE PERIPHERAL $sub 4$UNFED$sub 4$ CHANNEL

Description: The deviation from the expected coolant flow distribution within the SNAP 2 reactor is due to the filling and draining of the unfed'' peripheral flow channels. An analysis of the cross-flow in a simulated SNAP 2 model omitting the unfed'' peripheral channels was made. The results of this investigation are presented herein. (auth)
Date: February 20, 1964
Creator: Montgomery, L.D.
Partner: UNT Libraries Government Documents Department

Space Power Program, Instrumentation and Control System Architecture, Pre-conceptual Design, for Information

Description: The purpose of this letter is to forward the Prometheus preconceptual Instrumentation and Control (I&C) system architecture (Enclosure (1)) to NR for information as part of the Prometheus closeout work. The preconceptual 1&C system architecture was considered a key planning document for development of the I&C system for Project Prometheus. This architecture was intended to set the technical approach for the entire I&C system. It defines interfaces to other spacecraft systems, defines hardware blocks for future development, and provides a basis for accurate cost and schedule estimates. Since the system requirements are not known at this time, it was anticipated that the architecture would evolve as the design of the reactor module was matured.
Date: October 20, 2005
Creator: Ross, JM
Partner: UNT Libraries Government Documents Department

Space Shielding Materials for Prometheus Application

Description: At the time of Prometheus program restructuring, shield material and design screening efforts had progressed to the point where a down-selection from approximately eighty-eight materials to a set of five ''primary'' materials was in process. The primary materials were beryllium (Be), boron carbide (B{sub 4}C), tungsten (W), lithium hydride (LiH), and water (H{sub 2}O). The primary materials were judged to be sufficient to design a Prometheus shield--excluding structural and insulating materials, that had not been studied in detail. The foremost preconceptual shield concepts included: (1) a Be/B{sub 4}C/W/LiH shield; (2) a Be/B{sub 4}C/W shield; (3) and a Be/B{sub 4}C/H{sub 2}O shield. Since the shield design and materials studies were still preliminary, alternative materials (e.g., {sup nal}B or {sup 10}B metal) were still being screened, but at a low level of effort. Two competing low mass neutron shielding materials are included in the primary materials due to significant materials uncertainties in both. For LiH, irradiation-induced swelling was the key issue, whereas for H{sub 2}O, containment corrosion without active chemistry control was key, Although detailed design studies are required to accurately estimate the mass of shields based on either hydrogenous material, both are expected to be similar in mass, and lower mass than virtually any alternative. Unlike Be, W, and B{sub 4}C, which are not expected to have restrictive temperature limits, shield temperature limits and design accommodations are likely to be needed for either LiH or H{sub 2}O. The NRPCT focused efforts on understanding swelting of LiH, and observed, from approximately fifty prior irradiation tests, that either casting ar thorough out-gassing should reduce swelling. A potential contributor to LiH swelling appears to be LiOH contamination due to exposure to humid air, that can be eliminated by careful processing. To better understand LiH irradiation performance and mitigate the risks in LiH development for ...
Date: January 20, 2006
Creator: Lewis, R.
Partner: UNT Libraries Government Documents Department

Physical Property Changes in Plutonium from Accelerated Aging using Pu-238 Enrichment

Description: We present changes in volume, immersion density, and tensile properties observed from accelerated aged plutonium alloys. Accelerated alloys (or spiked alloys) are plutonium alloys enriched with approximately 7.5 weight percent of the faster-decaying {sup 238}Pu to accelerate the aging process by approximately 17 times the rate of unaged weapons-grade plutonium. After sixty equivalent years of aging on spiked alloys, the dilatometry shows the samples at 35 C have swelled in volume by 0.15 to 0.17 % and now exhibit a near linear volume increase due to helium in-growth. The immersion density of spiked alloys shows a decrease in density, similar normalized volumetric changes (expansion) for spiked alloys. Tensile tests show increasing yield and engineering ultimate strength as spiked alloys are aged.
Date: December 20, 2006
Creator: Chung, B W; Choi, B W; Saw, C K; Thompson, S R; Woods, C H; Hopkins, D J et al.
Partner: UNT Libraries Government Documents Department

SNAP I POWER CONVERSION SYSTEM TURBINE DEVELOPMENT. Period covered: February 1, 1957 to June 30, 1959

Description: Turbine development for the SNAP I power conversion system is described. A three-stage axial flow turbine with the first two impulse stages partial admission and the last stage full admission with a slight amount of reaction was selected. Other design and performance data are included. (J.R.D.)
Date: June 20, 1960
Creator: Reemsnyder, D.C. & Szanca, E.M.
Partner: UNT Libraries Government Documents Department

SNAP I POWER CONVERSION SYSTEM PUMP DEVELOPMENT. Period covered: February 1, 1957 to June 30, 1959

Description: S>Pump development for the SNAP I power conversion system is described. A four-vaned impeller pump supplemented by a jet boost stage was selected for development to meet the final design requirements. Information on other designs, pump test facilities, and conclusions are included. (J.R.D.)
Date: June 20, 1960
Partner: UNT Libraries Government Documents Department

SNAP I POWER CONVERSION SYSTEM MATERIALS DEVELOPMENT. Period covered: February 1, 1957 to June 30, 1959

Description: Investigations of materials for use in connection with the SNAP I mercury Rankine cycle power conversion system are discussed. Test programs are outlined and results are tabulated for each candidate material. Several nonmetallic materials and processing procedures were developed which enabled uncooled high-performance electric machinery to operate at 550 deg F in mercury vapor. (J.R.D.)
Date: June 20, 1960
Creator: Hambor, V.F. & Owens, J.J.
Partner: UNT Libraries Government Documents Department

SNAP I POWER CONVERSION SYSTEM DEVELOPMENT. Period covered: February 1, 1957 to June 30, 1959

Description: Development of the SNAP I power conversion system is described. The system is designed to convert the thermal energy produced by the decay of radioisotopes into 500 watts of electrical energy by means of a mercury Funkine cycle. A list of specific accomplishments of the program is included. (J.R.D.)
Date: June 20, 1960
Creator: Biering, R.C.; Carrell, D.D.; Grevstad, P.E.; Otto, N.P.; Picking, J.W.; Thur, G.M. et al.
Partner: UNT Libraries Government Documents Department

SNAP I POWER CONVERSION SYSTEM CONTROL DEVELOPMENT. Period covered: February 1, 1957 to June 30, 1959

Description: Development of the control elements for the SNAP 1 power conversion system is described. A description of test and prototype hardware and performance data are included. The control package in its final design is a combination of regulator and speed-sensitive feedback which provides satisfactory steady-state operation and serves as a mechanism correction for system disturbances. (J.R.D.)
Date: June 20, 1960
Creator: Dauterman, W.E.; Mueller, M.W. & Viton, E.J.
Partner: UNT Libraries Government Documents Department

SNAP I POWER CONVERSION SYSTEM CONDENSER RADIATOR DEVELOPMENT. Period covered: February 1, 1957 to April 15, 1959

Description: S>Development of the condenser-radiator for use in the SNAP I power conversion system is described. Although no prototype hardware was designed or tested in the program, the concept of rejecting waste by radiation in a gravitationless environment was proved feasible. (J.R.D.)
Date: June 20, 1960
Creator: Kiraly, R.J. & Reemsnyder, D.C.
Partner: UNT Libraries Government Documents Department

SNAP I POWER CONVERSION SYSTEM BEARINGS DEVELOPMENT. Period covered: February 1, 1957 to June 30, 1959

Description: Development of bearings for use in the SNAP I power conversion system is described. Liquid mercury, lubricated hydrosphere bearings were selected. Design and performance data are given along with conclusions. (J.R.D.)
Date: June 20, 1960
Creator: Meredith, R.; Ono, G.Y. & Reemsnyder, D.C.
Partner: UNT Libraries Government Documents Department

SNAP I POWER CONVERSION SYSTEM ALTERNATOR DEVELOPMENT. Period covered: February 1, 1957 to June 30, 1959

Description: Alternator development for the SNAP 1 power conversion system is described. A radial air-gap permanent-magnet 6-pole single-phase 2600-cps alternator, rated at 536 watts, 0.8 power factor, and 115 volts was selected. Discussion of requirements and specifications, design and performance, test facilities, and conclusions are included. (J.R.D.)
Date: June 20, 1960
Creator: Morgan, H.J.
Partner: UNT Libraries Government Documents Department

LCRE and SNAP 50-DR-1 programs. Engineering progress report, October 1, 1962--December 31, 1962

Description: Declassified 5 Sep 1973. Information is presented concerning LCRE specifications, reactor kinetics, fuel elements, primary coolant circuit, secondary coolant circuit, materials development, and fabrication; and SNAP50-DR- 1 specifications, primary pump, and materials development. (DCC)
Date: March 20, 1963
Partner: UNT Libraries Government Documents Department