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in subjects: "Irradiation Reactors"

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Seismic hazard evaluation for the high-flux isotope reactor (HFIR) Oak Ridge National Laboratory, Oak Ridge, Tennessee

This study investigates the probabilistic hazard of earthquake-induced ground shaking at the HFIR facility, Oak Ridge, Tennessee. These results will be used to calculate plant response and potential effects in a Probabilistic Risk Assessment (PRA). For this purpose, several guidelines apply to this work. First, both the frequency of exceedance and the uncertainty in frequency of exceedance of various ground motion levels must be represented. These are required by the PRA so that the frequency a… more

Date: September 1, 1991

Creator: McGuire, R.K. & Toro, G.R. (Risk Engineering, Inc., Golden, CO (United States))

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Preparation of curium-americium oxide microspheres by resin-bead loading

Resin-bead loading and calcination techniques have been used to produce all curium and americium oxide feed material (about 2.2 kg) for HFIR targets since 1971. The process based on Dowex 50W resin has progressed from a series of test runs, through special production runs, into routine production in permanent equipment beginning in 1975. Key attributes of this process are its reliability, high yields, and ease of operation. The process is suited for remote operation in hot cells. Yields approac… more

Date: January 1, 1980

Creator: Chattin, F. R.; Benker, D. E.; Lloyd, M. H.; Orr, P. B.; Ross, R. G. & Wiggins, J. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Feynmann variance-to-mean method

The Feynmann and other fluctuation techniques have been shown to be useful for determining the multiplication of subcritical systems. The moments of the counting distribution from neutron detectors is analyzed to yield the multiplication value. We present the methodology and some selected applications and results and comparisons with Monte Carlo calculations.

Date: January 1, 1985

Creator: Dowdy, E. J.; Hansen, G. E. & Robba, A. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Natural convection heat transfer analysis of ATR fuel elements

Natural convection air cooling of the Advanced Test Reactor (ATR) fuel assemblies is analyzed to determine the level of decay heat that can be removed without exceeding the melting temperature of the fuel. The study was conducted to assist in the level 2 PRA analysis of a hypothetical ATR water canal draining accident. The heat transfer process is characterized by a very low Rayleigh number (Ra {approx} 10{sup {minus}5}) and a high temperature ratio. Since neither data nor analytical models wer… more

Date: May 1, 1992

Creator: Langerman, M.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

High Flux Isotope Reactor. Quarterly report, October, November, and December 1979

Routine reactor operation with four end-of-cycle shutdowns and one scheduled midcycle shutdown resulted in an on-stream time of 93.6% for the quarter. This gave the HFIR an on-stream time for the year of 91.3%. The outer control plates were replaced, and the annual core components inspection was made.

Date: August 1, 1980

Creator: Corbett, B.L. & Poteet, K.H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Force analysis of the advanced neutron source control rod drive latch mechanism

The Advanced Neutron Source reactor (ANS), a proposed Department of Energy research reactor currently undergoing conceptual design at the Oak Ridge National Laboratory (ORNL), will generate a thermal neutron flux approximating 10{sup 30} M{sup {minus}2}{emdash}S{sup {minus}1}. The compact core necessary to produce this flux provides little space for the shim safety control rods, which are located in the central annulus of the core. Without proper control rod drive design, the control rod drive … more

Date: January 1, 1989

Creator: Damiano, B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Inspection methods for physical protection. Task II. Review of research reactor licensees' physical security practices

Security systems and security procedures for the AFRRI reactor, the University of Maryland TRIGA reactor, and the University of Virginia CAVALIER and UVAR reactors are described.

Date: July 3, 1980

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

High flux isotope reactor quarterly report, July, August, and September of 1981

Routine reactor operation with four end-of-cycle shutdowns and two unscheduled shutdowns resulted in an on-stream time of 91.3% for the quarter. The outer control plates and the inner control cylinder were changed and a semi-annual core component inspection was made.

Date: April 1, 1982

Creator: Corbett, B. L. & Poteet, K. H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Historical overview of domestic spent fuel shipments: Update

This report presents available historic data on most commercial and research reactor spent fuel shipments in the United States from 1964 through 1989. Data include sources of the spent fuel shipped, types of shipping casks used, number of fuel assemblies shipped, and number of shipments made. This report also addresses the shipment of spent research reactor fuel. These shipments have not been documented as well as commercial power reactor spent fuel shipment activity. Available data indicate th… more

Date: July 1, 1991

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Review of physics methodology of ATR safety analysis

At the request of EG G Idaho, the Pacific Northwest Laboratory (PNL) performed a brief review of the physics methods employed in the safety analyses for the Advanced Test Reactor. PNL determined that the general approach used by EG G was sound. Comparisons were made between the EG G results and a simplified PBL model. These demonstrated good agreement. However, the lack of spacial treatment of the moderator density reactivity coefficient and exclusion of the test loops from the reactivity model… more

Date: September 1, 1991

Creator: Little, W.W. & Heaberlin, S.W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Post-test examination observations for the W-2 SLSF experiment. [Sodium Loop Safety Facility]

Gamma scanning measurements revealed that the axial power profile in these test trains was more peaked than expected based on pretest calculations and critical facility measurements. These results implied that the thermal flux incident on the test assembly was greater than expected, which was manifested in highly skewed and extensive fuel melting zones in the outer pin fuel pellets. Observations indicated that the extent of fuel melting near the midplane exceeded 90% of the pellet radius in som… more

Date: September 1, 1983

Creator: Pitner, A. L.; Smith, D. E. & Culley, G. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Large break loss-of-coolant accident analyses for the high flux isotope reactor

The US Department of Energy's High Flux Isotope Reactor (HFIR) was analyzed to evaluate it's response to a spectrum of loss-of-coolant accidents (LOCAs) with potential for leading to core damage. The MELCOR severe accident analysis code (version 1.7.1) was used to evaluate the overall dynamic response of HFIR. Before conducting LOCA analyses, the steady-state thermal-hydraulic parameters evaluated by MELCOR for various loop sections were verified against steady-state operating data. Thereafter,… more

Date: January 1, 1989

Creator: Taleyarkhan, R.P. (Oak Ridge National Lab., TN (USA))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

High Flux Isotope Reactor. Quarterly report, July--September 1977

Routine reactor operation with three end-of-cycle shutdowns and the completion of a fourth carried over from the previous quarter resulted in an on-stream time of 95.5 percent. The control plates were changed, and a new inner control cylinder was installed. Basic operating data for the quarter are listed.

Date: December 1, 1977

Creator: Corbett, B. L.; McCord, R. V. & Poteet, K. H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Phase distribution measurements in narrow rectangular channels using image-processing techniques

Phase distribution of air-water flow in a narrow rectangular channel is examined using image-processing techniques. Ink is added to the water, and clear channel walls were used to allow high-speed, still photographs and video tape to be taken of the air-water flow field. Flow field images are digitized and stored in a Macintosh IIci computer using a frame grabber board. Local grey levels are related to liquid thickness in the flow channel using a calibration fixture. Image-processing shareware … more

Date: June 1, 1992

Creator: Bentley, C. L. & Ruggles, A. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Experience in the separation and purification of transplutonium elements in the transuranium processing plant at the Oak Ridge National Laboratory

Since 1966, TRU has been the main center of production for transcurium elements in the US, producing 460 mg /sup 249/Bk, 4 g /sup 252/Cf, 18 mg /sup 253/Es, and 10 pg /sup 257/Fm. During the 14 years operation, 39 chemical processing campaigns were conducted to process 265 HFIR targets and 195 SRP production reactor targets. (DLC)

Date: January 1, 1980

Creator: King, L. J.; Bigelow, J. E. & Collins, E. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

High flux isotope reactor technical specifications

Technical specifications are presented concerning safety limits and limiting safety system settings; limiting conditions for operation; surveillance requirements; design features; administrative controls; and accidents and anticipated transients.

Date: April 1, 1982

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Preliminary risks associated with postulated tritium release from production reactor operation

The Probabilistic Risk Assessment (PRA) of Savannah River Plant (SRP) reactor operation is assessing the off-site risk due to tritium releases during postulated full or partial loss of heavy water moderator accidents. Other sources of tritium in the reactor are less likely to contribute to off-site risk in non-fuel melting accident scenarios. Preliminary determination of the frequency of average partial moderator loss (including incidents with leaks as small as .5 kg) yields an estimate of /app… more

Date: January 1, 1988

Creator: O'Kula, K.R. & Horton, W.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Advanced Test Reactor Probabilistic Risk Assessment Methodology and Results Summary

The Advanced Test Reactor (ATR) probabilistic risk assessment (PRA) Level 1 report documents a comprehensive and state-of-the-art study to establish and reduce the risk associated with operation of the ATR, expressed as a mean frequency of fuel damage. The ATR Level 1 PRA effort is unique and outstanding because of its consistent and state-of-the-art treatment of all facets of the risk study, its comprehensive and cost-effective risk reduction effort while the risk baseline was being establishe… more

Date: January 1, 1992

Creator: Eide, S. A.; Atkinson, S. A. & Thatcher, T. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Experimental facilities

We have completed an engineering feasibility study of a major modification of the HFIR facility and are now beginning a similar study of an entirely new facility. The design of the reactor itself is common to both options. In this paper, a general description of the modified HFIR is presented with some indications of the additional facilities that might be available in an entirely new facility.

Date: January 1, 1984

Creator: Moon, R.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

(Fission product transport experiments (HFR-B1))

Travel to the JRC Petten was for the purpose of discussing the HFR-B1 experiment and post irradiation activities. Technical assessment of the experiment strongly supports the concept of enhanced fission gas release at temperatures above 1100{degree}C, the extensive release of stored fission gas at water vapor levels postulated in accident scenarios, an increase in the steady-state fission gas release under hydrolyzing conditions, and an increase in gas release during thermal cycling. Schedules … more

Date: December 5, 1989

Creator: Myers, B.F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Neutronic analysis of the JMTR with LEU fuel and burnable poison

The results of neutronics calculations are presented for the JMTR equilibrium core with LEU silicide fuel, boron and cadmium burnable poisons in the sideplates, and a cycle length of 24 days instead of 11 days with the current HEU fuel. The data indicate that several options are feasible provided that silicide fuels with high uranium densities are successfully demonstrated and licensed. 2 refs., 10 figs., 5 tabs.

Date: January 1, 1984

Creator: Nagaoka, Yoshiharu; Oyamada, Rokuro; Matos, J.E. & Woodruff, W.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Production of transplutonium elements in the high flux isotope reactor (HFIR)

The techniques described have been demonstrated to be adequate to predict the contents of transplutonium element production targets which have been irradiated in the HFIR. The deviations, at least for isotopes of mass 253 or less, are generally within the usual analytical uncertainties, or else are for isiotopes which are of little overall import to the program. Work is especially needed to get a better picture of the production of /sup 250/Cm, /sup 254/Es, /sup 255/Es, and ultimately /sup 257/… more

Date: January 1, 1980

Creator: Bigelow, J. E.; Corbett, B. L.; King, L. J.; McGuire, S. C. & Sims, T. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Heated uranium tetrafluoride target system to release non-rare gas fission products for the TRISTAN isotope separator. [As replacement for uranyl stearate]

Off-line experiments indicated that fluorides of As, Se, Br, Kr, Zr, Nb, Mo, Tc, Ru, Sb, Te, I and Xe could be volatilized, but except for Br, Kr, I and Xe, none of these elements were observed after mass separation in the on-line experiments. The results of the on-line experiments indicated a very low level of hydride contamination at ambient temperature and consequently, uranium tetrafluoride replaced uranyl stearate as the primary gaseous fission product target. Possible reasons for the fail… more

Date: October 1, 1977

Creator: Gill, R. L.

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

open access

Examination of T-111 clad uranium nitride fuel pins irradiated up to 13,000 hours at a clad temperature of 990/sup 0/C

The examination of 27 fuel pins irradiated in the Plum Brook reactor facility is described. Curtailment of NASA sponsored nuclear programs prevented a complete examination of all pins. Nevertheless, results include fuel pin integrity, clad ductility, clad strain, fission gas release, fuel burnup, fuel swelling, neutron fluence, metallography, and instrumentation reliability. Twenty-two fuel pins were tested for fission gas leaks; 13 pins leaked with two having visible cracks. Fuel swelling appe… more

Date: September 10, 1973

Creator: Slaby, J.G.; Siegel, B.L.; Bowles, K.J. & Galbo, R.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department