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Thulium-170 heat source

Description: An isotopic heat source is formed using stacks of thin individual layers of a refractory isotopic fuel, preferably thulium oxide, alternating with layers of a low atomic weight diluent, preferably graphite. The graphite serves several functions: to act as a moderator during neutron irradiation, to minimize bremsstrahlung radiation, and to facilitate heat transfer. The fuel stacks are inserted into a heat block, which is encased in a sealed, insulated and shielded structural container. Heat pipe… more
Date: September 6, 1990
Creator: Walter, Carl E.; Van Konynenburg, Richard & VanSant, James H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Low enrichment fuel conversion for Iowa State University

Description: Work during the reported period was centered primarily in preparation for receiving the LEU fuel and the shipping of the HEU fuel. The LEU fuel has not been received. The HEU fuel assemblies for the UTR-10 reactor will not fit into any current research reactor shipping containers; therefore, the fuel assemblies must be disassembled and the fuel shipped as fuel plates. Procedures and practices have been developed so that the fuel assemblies will be disassembled in a shielded environment.
Date: August 1, 1990
Creator: Rohach, A.F. & Hendrickson, R.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Technical considerations for evaluating substantially complete containment of high-level waste within the waste package

Description: This report deals with technical information that is considered essential for demonstrating the ability of the high-level radioactive waste package to provide substantially complete containment'' of its contents (vitrified waste form or spent light-water reactor fuel) for a period of 300 to 1000 years in a geological repository environment. The discussion is centered around technical considerations of the repository environment, materials and fabrication processes for the waste package componen… more
Date: December 1, 1990
Creator: Manaktala, H.K. (Southwest Research Inst., San Antonio, TX (USA). Center for Nuclear Waste Regulatory Analyses) & Interrante, C.G. (Nuclear Regulatory Commission, Washington, DC (USA). Div. of High-Level Waste Management)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparison of beryllium and graphite first-walls in JET

Description: JET has operated with beryllium as a first-wall material in 1989 and 1990. An initial period with beryllium evaporation onto the original graphite surfaces was followed by operation with beryllium belt-limiter tiles. Beryllium Faraday shields for the ICRH antennae and lower X-point target tiles were installed for experiments in 1990. The use of beryllium has increased the density limit, significantly reduced deconditioning following disruptions, allowed heavy gas fueling for impurity control, r… more
Date: January 1, 1990
Creator: Thomas, P. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

MHTGR product distinction

Description: Commercial power reactor operating experience and regulatory practice in the United States is dominated by Light Water Reactor (LWR) technology. This experience base and regulatory structure is a point of departure for the development of any future nuclear option, and must be understood and utilized as appropriate. This report discusses experience with current generation plants considered relevant to MHTGR development, as well as the fundamental differences between the MHTGR and LWR technology,… more
Date: December 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Chernobyl source term estimation

Description: The Chernobyl source term available for long-range transport was estimated by integration of radiological measurements with atmospheric dispersion modeling and by reactor core radionuclide inventory estimation in conjunction with WASH-1400 release fractions associated with specific chemical groups. The model simulations revealed that the radioactive cloud became segmented during the first day, with the lower section heading toward Scandinavia and the upper part heading in a southeasterly direct… more
Date: September 1, 1990
Creator: Gudiksen, P. H.; Harvey, T. F. & Lange, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Divertor-plasma studies on DIII-D

Description: This paper presents an overview of recent results from divertor physics studies in DIII-D. Heat flux measurements at input power levels up to 20 MW show that steady divertor heat loads of up to 4 MW/m{sup 2} are obtained in H-mode discharges with ELMs. No carbon blooms are observed. The heat flux profile is highly peaked at the outside strike point in single-null discharges, and is up/down asymmetric in double-null discharges. Recent experiments with gas injection below the X-point have demonst… more
Date: November 1, 1990
Creator: Hill, D. N; Futch, A.; Porter, G.; Rensink, M. E.; Rognlien, T. (Lawrence Livermore National Lab., CA (USA)); Petrie, T. W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Contributions of chemistry in early day Los Alamos

Description: During 1943--1945, the premier physics laboratory in the world was at Los Alamos, but chemistry contributions were vital. Major chemical impacts on the success of the Los Alamos wartime mission included electrochemistry, which found the true melting point of plutonium metal to be hundreds of degrees lower than anticipated. This discovery had profound simplifying effects regarding crucibles to contain molten plutonium and on its production. Other significant chemical contributions involved const… more
Date: January 1, 1990
Creator: Penneman, R.A. & Meade, R.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Proceedings of the Office of Fusion Energy/DOE workshop on ceramic matrix composites for structural applications in fusion reactors

Description: A workshop to assess the potential application of ceramic matrix composites (CMCs) for structural applications in fusion reactors was held on May 21--22, 1990, at University of California, Santa Barbara. Participants included individuals familiar with materials and design requirements in fusion reactors, ceramic composite processing and properties and radiation effects. The primary focus was to list the feasibility issues that might limit the application of these materials in fusion reactors. C… more
Date: November 1, 1990
Creator: Jones, R.H. (Pacific Northwest Lab., Richland, WA (USA)) & Lucas, G.E. (California Univ., Santa Barbara, CA (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Thermal sweeping analysis for divertor plate materials

Description: Magnetically sweeping the separatrix along the divertor plate is proposed to accommodate higher heat loads or to reduce the maximum armor/coatings surface temperature for a given heat flux distribution. During the sweeping, each position on the divertor plate will experience periodic heat and particle flux variations. The magnitude of these variations with time will depend on the location as well as on the time shape of the sweeping wave. Consequently, the shape of the sweeping pulse and the sw… more
Date: September 1, 1990
Creator: Hassanein, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Metallic phase-change materials for solar dynamic energy storage systems

Description: Solar (thermal) dynamic power systems for satellites require a heat storage system that is capable of operating the engine during eclipse. The conventional approach to this thermal storage problem is to use the latent heat of fluoride salts, which would melt during insolation and freeze during eclipse. Although candidate fluorides have large heats of fusion per unit mass, their poor thermal conductivity limits the rate at which energy can be transferred to and from the storage device. System pe… more
Date: December 1, 1990
Creator: Lauf, R.J. & Hamby, C. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High density regimes and beta limits in JET

Description: Results are first presented on the density limit in JET discharges with graphite (C), Be gettered graphite and Be limiters. There is a clear improvement in the case of Be limiters. The Be gettered phase showed no increase in the gas fueled density limit, except with Ion Cyclotron Resonance Heating (ICRH), but, the limit changed character. During MARFE-formation, any further increase in density was prevented, leading to a soft density limit. The soft density limit was a function of input power a… more
Date: January 1, 1990
Creator: Smeulders, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Advanced infrared optically black baffle materials

Description: Infrared optically black baffle surfaces are an essential component of many advanced optical systems. All internal surfaces in advanced infrared optical sensors that require stray light management to achieve resolution are of primary concern in baffle design. Current industrial materials need improvements to meet advanced optical sensor systems requirements for optical, survivability, and endurability. Baffles are required to survive and operate in potentially severe environments. Robust diffus… more
Date: January 1, 1990
Creator: Seals, R.D.; Egert, C.M. (Oak Ridge National Lab., TN (USA)) & Allred, D.D. (Brigham Young Univ., Provo, UT (USA). Dept. of Physics and Astronomy)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Fuel damage during off-normal transients in metal-fueled fast reactors

Description: Fuel damage during off-normal transients is a key issue in the safety of fast reactors because the fuel pin cladding provides the primary barrier to the release of radioactive materials. Part of the Safety Task of the Integral Fast Reactor Program is to provide assessments of the damage and margins to failure for metallic fuels over the wide range of transients that must be considered in safety analyses. This paper reviews the current status of the analytical and experimental programs that are … more
Date: 1990
Creator: Kramer, J. M. & Bauer, T. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Transient feedback from fuel motion in metal IFR (Integral Fast Reactor) fuel

Description: Results from hodoscope data analyses are presented for TREAT transient-overpower tests M5 through M7 with emphasis on transient feedback mechanisms, including prefailure expansion at the tops of the fuel pins, subsequent dispersive axial fuel motion, and losses in relative worth of the fuel pins during the tests. Tests M5 and M6 were the first TOP tests of margin to cladding branch and prefailure elongation of D9-clad ternary (U-Pu-Zr) IFR-type fuel. Test M7 extended these results to high-burnu… more
Date: January 1, 1990
Creator: Rhodes, E.A.; Stanford, G.S.; Regis, J.P.; Bauer, T.H. & Dickerman, C.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Accident progression event tree analysis for postulated severe accidents at N Reactor

Description: A Level II/III probabilistic risk assessment (PRA) has been performed for N Reactor, a Department of Energy (DOE) production reactor located on the Hanford reservation in Washington. The accident progression analysis documented in this report determines how core damage accidents identified in the Level I PRA progress from fuel damage to confinement response and potential releases the environment. The objectives of the study are to generate accident progression data for the Level II/III PRA sour… more
Date: June 1, 1990
Creator: Wyss, G. D.; Camp, A. L.; Miller, L. A.; Dingman, S. E.; Kunsman, D. M. & Medford, G. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Modeling and performance of the MHTGR (Modular High-Temperature Gas-Cooled Reactor) reactor cavity cooling system

Description: The Reactor Cavity Cooling System (RCCS) of the Modular High- Temperature Gas-Cooled Reactor (MHTGR) proposed by the U.S. Department of Energy is designed to remove the nuclear afterheat passively in the event that neither the heat transport system nor the shutdown cooling circulator subsystem is available. A computer dynamic simulation for the physical and mathematical modeling of and RCCS is described here. Two conclusions can be made form computations performed under the assumption of a unif… more
Date: April 1, 1990
Creator: Conklin, J. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Bounding core temperature transients for severe and rapid water ingress scenarios in modular high temperature gas-cooled reactors

Description: A rapid water ingress transient, resulting from steam generator tube or tube-sheet failures, could lead to a reactivity insertion and core heatup in the Modular High Temperature Gas-Cooled Reactors. This paper considers the effect of hypothetical rapid and severe water ingress scenarios of extremely low probability, and assesses the effect of such transients on potentially excessive fuel temperatures and subsequent fuel failures. The results indicate that for the worst postulated scenarios the … more
Date: January 1, 1990
Creator: Kroeger, P. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tomographic imaging of severely disrupted fuel assemblies tested in TREAT

Description: A series of CT codes is under development in the Reactor Analysis and Safety Division of Argonne National Laboratory for use as a post-test examination tool to analyze segments of the final fuel-bundle configuration of TREAT tests. This paper presents the results of CT analysis for fuel assemblies using neutron radiography. Fuel relocation following overpower transients in the TREAT reactor is examined for sections of the assemblies, and results are compared to metallographic sections. Further … more
Date: January 1, 1990
Creator: Morman, J. A.; Froehle, P. H.; Holland, J. W. & Bennett, J. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A vectorized heat transfer model for solid reactor cores

Description: The new generation of nuclear reactors includes designs that are significantly different from light water reactors. Among these new reactor designs is the Modular High-Temperature Gas-Cooled Reactor (MHTGR). In addition, nuclear thermal rockets share a number of similarities with terrestrial HTGRs and would be amenable to similar types of analyses. In these reactors, the heat transfer in the solid core mass is of primary interest in design and safety assessment. One significant safety feature o… more
Date: January 1, 1990
Creator: Rider, W. J.; Cappiello, M. W. & Liles, D. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Office of Analysis and Evaluation of Operational Data 1989 annual report, Power reactors

Description: The annual report of the US Nuclear Regulatory Commission's Office for Analysis and Evaluation of Operational Data (AEOD) is devoted to the activities performed during 1989. The report is published in two separate parts. This document, NUREG-1272, Vol. 4, No. 1, covers power reactors and presents an overview of the operating experience of the nuclear power industry from the NRC perspective, including comments about the trends of some key performance measures. The report also includes the princi… more
Date: July 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Infrared thermography system on DIII-D

Description: Six infrared cameras measure temperature changes on the protective graphite armor inside the DIII-D vacuum vessel. Simultaneous time dependent temperature measurements are made on armor tiles located on the centerpost and divertor regions, and on both outboard limiters. The nearly-complete poloidal coverage is useful in measuring both the plasma heat flux distributions inside the vessel and the plasma power balance. Spatial resolution of each camera system is {approx lt}1 cm, while the minimum … more
Date: October 1, 1990
Creator: Petrie, T.W. (General Atomics, San Diego, CA (USA)); Hill, D.N.; Baptista, J. & Brown, M. (Lawrence Livermore National Lab., CA (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fast reactor safety testing in Transient Reactor Test (TREAT) in the 1980s

Description: Several series of fast reactor safety tests were performed in TREAT during the 1980s. These focused on the transient behavior of full-length oxide fuels (US reference, UK reference, and US advanced design) and on modern metallic fuels. Most of the tests addressed fuel behavior under transient overpower or loss-of-flow conditions. The test series were the PFR/TREAT tests; the RFT, TS, CDT, and RX series on oxide fuels; and the M series on metallic fuels. These are described in terms of their pri… more
Date: January 1, 1990
Creator: Wright, A.E. (Argonne National Lab., IL (USA)); Dutt, D.S. (Westinghouse Hanford Co., Richland, WA (USA)) & Harrison, L.J. (Argonne National Lab., Idaho Falls, ID (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Evaluation of graphite/steam interactions for ITER (International Thermonuclear Experimental Reactor)

Description: In this report we present the results of an experimental/analytical study designed to determine the quantity of hydrogen generated during a coolant inleakage accident in ITER. This hydrogen could represent a potential explosive hazard, provided the proper conditions exist, causing machine damage and release of radioactive material. We have measured graphite/steam reaction rates for several graphites and carbon-based composites at temperatures between 1000 C and 1700 C. The effects of steam flow… more
Date: September 1, 1990
Creator: Smolik, G. R.; Merrill, B. J.; Piet, S. J. & Holland, D. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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