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Critical Experiments With Arrays of Orr and Bsr Fuel Elements

Description: Critical experiments were performed with ORR and BSR fuel elements to determine safe arrays in which the elements could be handled and stored. The data indicate that the optimum spacing for criticality of 168-g ORR elements in water is 0.2 in. between locating bosses annd that an infinite array of vertically placed elements onc element high would probably be subcritical with a 1 1/2-in. spacing between locating bosses. For uniform arrays of adjacent elements in water, variation in thc fuel load… more
Date: October 1, 1958
Creator: Fox, J. K. & Gilley, L. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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LCEs for Naval Reactor Benchmark Calculations

Description: The purpose of this engineering calculation is to document the MCNP4B2LV evaluations of Laboratory Critical Experiments (LCEs) performed as part of the Disposal Criticality Analysis Methodology program. LCE evaluations documented in this report were performed for 22 different cases with varied design parameters. Some of these LCEs (10) are documented in existing references (Ref. 7.1 and 7.2), but were re-run for this calculation file using more neutron histories. The objective of this analysis … more
Date: July 19, 1999
Creator: Anderson, W.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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CRITICALITY CALCULATION FOR THE MOST REACTIVE DEGRADED CONFIGURATIONS OF THE FFTF SNF CODISPOSAL WP CONTAINING AN INTACT IDENT-69 CONTAINER

Description: The objective of this calculation is to perform additional degraded mode criticality evaluations of the Department of Energy's (DOE) Fast Flux Test Facility (FFTF) Spent Nuclear Fuel (SNF) codisposed in a 5-Defense High-Level Waste (5-DHLW) Waste Package (WP). The scope of this calculation is limited to the most reactive degraded configurations of the codisposal WP with an almost intact Ident-69 container (breached and flooded but otherwise non-degraded) containing intact FFTF SNF pins. The con… more
Date: August 28, 2002
Creator: Moscalu, D.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Scale-4 analysis of pressurized water reactor critical configurations: Volume 5, North Anna Unit 1 Cycle 5

Description: ANSI/ANS 8.1 requires that calculational methods for away-from- reactor (AFR) criticality safety analyses be validated against experiment. This report summarizes part of the ongoing effort to benchmark AFR criticality analysis methods using selected critical configurations from commercial PWRs. Codes and data in the SCALE-4 code system were used. This volume documents the SCALE system analysis of one reactor critical configuration for North Anna Unit 1 Cycle 5. The KENO V.a criticality calculat… more
Date: October 1, 1996
Creator: Bowman, S.M. & Suto, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Further investigation of spectral temperature feedbacks

Description: This paper serves two purposes: (1) to introduce some new calculations of the temperature coefficients for uranium solutions, and (2) to examine some simplified calculations based on earlier work. Uranium solutions, while never having positive temperature coefficients, show trends in the feedback coefficient as a function of solution concentration that are similar to those seen for plutonium solutions. For both the plutonium and uranium solutions, the feedback coefficient experiences a local mi… more
Date: November 1, 1997
Creator: Kornreich, D.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Computation Results from a Parametric Study to Determine Bounding Critical Systems of Homogeneously Water-Moderated Mixed Plutonium--Uranium Oxides

Description: This report provides computational results of an extensive study to examine the following: (1) infinite media neutron-multiplication factors; (2) material bucklings; (3) bounding infinite media critical concentrations; (4) bounding finite critical dimensions of water-reflected and homogeneously water-moderated one-dimensional systems (i.e., spheres, cylinders of infinite length, and slabs that are infinite in two dimensions) that were comprised of various proportions and densities of plutonium … more
Date: January 11, 2001
Creator: Shimizu, Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Coupling parameters for partially reflected reactors

Description: For situations in which the standard point kinetic model does not adequately characterize the kinetic behavior of a reflected system, the Avery-Cohn differential equations can be used. However, these equations require that one determine the coupling parameters between the core and the reflector, f{sub cr} and f{sub rc}. The coupling parameter, f{sub cr}, represents the probability that a neutron in the core will leak into the reflector, and the coupling parameter, f{sub rc}, represents the prob… more
Date: July 1, 1995
Creator: Busch, R. D. & Spriggs, G. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The relationship between neutron multiplication and k{sub eff}

Description: In recent years the International Criticality Safety Benchmark Evaluation Project under the sponsorship of the Department of Energy has undertaken the task of evaluating past critical experiments. Many of the experiments involving metals were subcritical with extrapolation to some critical characteristic dimension. The metal experiments were commonly limited to a maximum multiplication of 100 for obvious safety considerations. Also many critical experiments often used subcritical measurements t… more
Date: September 1995
Creator: Brewer, R. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Enrico Fermi Fast Reactor Spent Nuclear Fuel Criticality Calculations: Degraded Mode

Description: The objective of this calculation is to characterize the nuclear criticality safety concerns associated with the codisposal of the Department of Energy's (DOE) Enrico Fermi (EF) Spent Nuclear Fuel (SNF) in a 5-Defense High-Level Waste (5-DHLW) Waste Package (WP) and placed in a Monitored Geologic Repository (MGR). The scope of this calculation is limited to the determination of the effective neutron multiplication factor (k{sub eff}) for the degraded mode internal configurations of the codispos… more
Date: July 21, 2000
Creator: Moscalu, D.R.; Angers, L.; Monroe-Rammsey, J. & Radulesca, H.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Isotopic Bias and Uncertainty for Burnup Credit Applications

Description: The application of burnup credit requires calculating the isotopic inventory of the irradiated fuel. The depletion calculation simulates the burnup of the fuel under reactor operating conditions. The result of the depletion analysis is the predicted isotopic composition, which is ultimately input to a criticality analysis to determine the system multiplication factor (k{sub eff}). This paper demonstrates an approach for calculating the isotopic bias and uncertainty in k{sub eff} for commercial … more
Date: August 19, 2002
Creator: Scaglione, J.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Two-dimensional benchmark calculations for PNL-30 through PNL-35

Description: Interest in critical experiments with lattices of mixed-oxide (MOX) fuel pins has been revived by the possibility that light water reactors will be used for disposition of weapons-grade plutonium. A series of six experiments with MOX lattices, designated PNL-30 through PNL-35, was performed at Pacific Northwest Laboratories in 1975 and 1976, and a set of benchmark specifications for these experiments subsequently was adopted by the Cross Section Evaluation Working Group (CSEWG). Although there … more
Date: September 1, 1997
Creator: Mosteller, R.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Extrapolations to critical for systems with large inherent sources

Description: An approach to delayed critical experiment was performed in 1981 at Pacific Northwest Laboratory with a cylindrical tank of plutonium-uranium nitrate solution. During this experiment, various methods to determine the critical height were used, including (1) extrapolation of the usual plot of inverse count rate vs. height, which estimates the delayed critical height (DCH); (2) the inverse count rate vs. height divided by count rate, which corrects somewhat for the change in inherent source size … more
Date: July 1997
Creator: Mihalczo, J. T. & Wyatt, M. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Physical Models and Statistical Procedures Used in the RACER Monte Carlo Code

Description: This report describes the MCV (Monte Carlo - Vectorized)Monte Carlo neutron transport code [Brown, 1982, 1983; Brown and Mendelson, 1984a]. MCV is a module in the RACER system of codes that is used for Monte Carlo reactor physics analysis. The MCV module contains all of the neutron transport and statistical analysis functions of the system, while other modules perform various input-related functions such as geometry description, material assignment, output edit specification, etc. MCV is very c… more
Date: July 1, 1999
Creator: Sutton, T. M.; Brown, F. B.; Bischoff, F. G.; MacMillan, D. B.; Ellis, C. L.; Ward, J. T. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of assembly local power distribution on storage rack criticality

Description: Fuel storage rack criticality calculations have been performed for a set of 8 x 8 BWR k/sub infinity/-equivalent fuel bundles. The results of these calculations indicate that the storage rack multiplication factor is not determined solely by the k/sub infinity/'s of the individual fuel assemblies, but is also sensitive to the local power, and underlying enrichment, burnable poison, water hole and burnup distributions. Furthermore, in order to insure a true conservative upper bound on the storag… more
Date: January 1, 1985
Creator: Todosow, M. & Carew, J.F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Critical Concentration Of Uranium Solution

Description: The experiments with U(37)O{sub 2}F{sub 2} aqueous solution followed the series of experiments with {sup 233}UO{sub 2}(NO{sub 3}){sub 2} and U(93)O{sub 2}(NO{sub 3}){sub 2} solutions in the 69.2-cm-diam sphere. The critical concentrations of {sup 233}U and {sup 235}U were used to evaluate the ratio of {ovr {eta}{sigma}{sub a}}(233)/{ovr {eta}{sigma}{sub a}}(235) some years ago when the accepted value of {ovr {eta}}(233) was questioned. The purpose of the experiment reported here was to measure … more
Date: November 3, 1973
Creator: Magnuson, D. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Summary Report of Laboratory Critical Experiment Analyses Performed for the Disposal Criticality Analysis Methodology

Description: This report, ''Summary Report of Laboratory Critical Experiment Analyses Performed for the Disposal Criticality Analysis Methodology'', contains a summary of the laboratory critical experiment (LCE) analyses used to support the validation of the disposal criticality analysis methodology. The objective of this report is to present a summary of the LCE analyses' results. These results demonstrate the ability of MCNP to accurately predict the critical multiplication factor (keff) for fuel with dif… more
Date: September 9, 1999
Creator: Scaglione, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Criticality Model Report

Description: The purpose of the ''Criticality Model Report'' is to validate the MCNP (CRWMS M&O 1998h) code's ability to accurately predict the effective neutron multiplication factor (k{sub eff}) for a range of conditions spanned by various critical configurations representative of the potential configurations commercial reactor assemblies stored in a waste package may take. Results of this work are an indication of the accuracy of MCNP for calculating eigenvalues, which will be used as input for criti… more
Date: March 12, 2003
Creator: Scaglione, J.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaluation of Calandria, Thimble, and Canned-Moderator Concepts for Sodium Graphite Reactors

Description: In efforts to improve the neutron economy and lower the capital costs of sodium graphite reactors, several methods of separating the sodium and graphite were investigated including the calandria, the thimble, and the canned moderator reactors. An analysis including nuclear, heat transfer, and economic comparisons was made of these SGR concepts. Based upon neutron economy and feasibility of core fabrication, the calandria concept appears to offer the greatest potential for improvement in 8GR des… more
Date: June 10, 1960
Creator: Reed, G.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear Characteristics of Cylindrical Breeder Reactors Containing Thorium in Pellet Form

Description: The results of nuclear calculations for aqueous homogeneous reactors containing blanket thorium in pellet form are presented. Critical core fuel concentrations, gross breeding ratios, power densities, and multiplication as dependent on core fuel concentration and neutron balances are included. Critical U/sup 233/ core concentration for a 24in.-diam. core was 8.4 gm/l when U/Th was 0.003 in the blanket and the relative power density at the core wall was 1.04 kw/ l/Mw. A 48-in.-diam. core require… more
Date: May 1, 1960
Creator: Vondy, D. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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TWODANT benchmark. Progress report

Description: TWODANT (Two-Dimensional, Diffusion-Accelerated, Neutral-Particle Transport) code has been benchmarked against 6 critical experiments (Jezebel plutonium critical assembly) and their k effective values compared with those of KENO and MCNP codes.
Date: January 11, 1994
Creator: Lee, Sung
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Addressing the Axial Burnup Distribution in PWR Burnup Credit Criticality Safety

Description: This paper summarizes efforts related to developing a technically justifiable approach for addressing the axial burnup distribution in PWR burnup-credit criticality safety analyses. The paper reviews available data on the axial variation in burnup and the effect of axial burnup profiles on reactivity in a SNF cask. A publicly available database of profiles is examined to identify profiles that maximize the neutron multiplication factor, k{sub eff}, assess its adequacy for general PWR burnup cre… more
Date: August 2, 2001
Creator: Wagner, J. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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