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Title: Subcriticality of two uranyl nitrate flat cylindrical tanks spaced in air by [sup 252]Cf-source-driven noise analysis

Abstract

The subcritical neutron multiplication factors k for two parallel, axially separated, flat cylindrical tanks separated up to 57.91cm in air and containing enriched uranyl (93.1 wt% [sup 235]U) nitrate solution (71.6-cm-i.d. tanks, 8.91-cm solution thickness, 1.555 g/cm[sup 3] solution density, and 404g U/l uranium density) were measured by the [sup 252]Cf-source-driven noise analysis method with measured k values varying from 0.99 to 0.80. These measurements were performed at the Los Alamos National Laboratory (LANL) Critical Experiments Facility in 1989 and were part of the program of Westinghouse Idaho Nuclear Company (WINCO) to benchmark calculations for the design of the new storage system at Idaho National Engineering Laboratory. Initial subcriticality measurements by the source-jerk method at LANL had indicated that at a calculated neutron multiplication factor k = 0.95, the measured k was 0.975. This discrepancy was of concern to WINCO because the new storage facility was being designed with a k limit of 0.95, and thus, half of the criticality safety margin of the storage design was equal to the discrepancy between early measurements and calculations. The [sup 252]Cf-source-driven noise analysis measurements confirmed the validity of the calculational methods. In addition to providing the neutron multiplication factor from point-kinetics interpretationmore » of the data, these measurements also provided the auto-power and cross-power spectral densities as a function of frequency, which can be calculated directly with recently developed Monte Carlo methods and thus could also be used to validate calculational methods and cross-section sets.« less

Authors:
; ; ; ;  [1]
  1. Oak Ridge National Lab., TN (United States)
Publication Date:
OSTI Identifier:
5982020
DOE Contract Number:  
AC05-84OR21400
Resource Type:
Journal Article
Journal Name:
Nuclear Technology; (United States)
Additional Journal Information:
Journal Volume: 103:3; Journal ID: ISSN 0029-5450
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; 11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; IDAHO NATIONAL ENGINEERING LABORATORY; STORAGE FACILITIES; DESIGN; URANYL NITRATES; SUBCRITICALITY; BENCHMARKS; MULTIPLICATION FACTORS; POSITIONING; SAFETY; TANKS; ZERO POWER REACTORS; ACTINIDE COMPOUNDS; CONTAINERS; EXPERIMENTAL REACTORS; NATIONAL ORGANIZATIONS; NITRATES; NITROGEN COMPOUNDS; OXYGEN COMPOUNDS; REACTORS; RESEARCH AND TEST REACTORS; URANIUM COMPOUNDS; URANYL COMPOUNDS; US DOE; US ERDA; US ORGANIZATIONS; 420203* - Engineering- Handling Equipment & Procedures; 050900 - Nuclear Fuels- Transport, Handling, & Storage

Citation Formats

Mihalczo, J T, Blakeman, E D, Pare, V K, Valentine, T E, and Auslander, D J. Subcriticality of two uranyl nitrate flat cylindrical tanks spaced in air by [sup 252]Cf-source-driven noise analysis. United States: N. p., 1993. Web. doi:10.13182/NT93-3.
Mihalczo, J T, Blakeman, E D, Pare, V K, Valentine, T E, & Auslander, D J. Subcriticality of two uranyl nitrate flat cylindrical tanks spaced in air by [sup 252]Cf-source-driven noise analysis. United States. https://doi.org/10.13182/NT93-3
Mihalczo, J T, Blakeman, E D, Pare, V K, Valentine, T E, and Auslander, D J. 1993. "Subcriticality of two uranyl nitrate flat cylindrical tanks spaced in air by [sup 252]Cf-source-driven noise analysis". United States. https://doi.org/10.13182/NT93-3.
@article{osti_5982020,
title = {Subcriticality of two uranyl nitrate flat cylindrical tanks spaced in air by [sup 252]Cf-source-driven noise analysis},
author = {Mihalczo, J T and Blakeman, E D and Pare, V K and Valentine, T E and Auslander, D J},
abstractNote = {The subcritical neutron multiplication factors k for two parallel, axially separated, flat cylindrical tanks separated up to 57.91cm in air and containing enriched uranyl (93.1 wt% [sup 235]U) nitrate solution (71.6-cm-i.d. tanks, 8.91-cm solution thickness, 1.555 g/cm[sup 3] solution density, and 404g U/l uranium density) were measured by the [sup 252]Cf-source-driven noise analysis method with measured k values varying from 0.99 to 0.80. These measurements were performed at the Los Alamos National Laboratory (LANL) Critical Experiments Facility in 1989 and were part of the program of Westinghouse Idaho Nuclear Company (WINCO) to benchmark calculations for the design of the new storage system at Idaho National Engineering Laboratory. Initial subcriticality measurements by the source-jerk method at LANL had indicated that at a calculated neutron multiplication factor k = 0.95, the measured k was 0.975. This discrepancy was of concern to WINCO because the new storage facility was being designed with a k limit of 0.95, and thus, half of the criticality safety margin of the storage design was equal to the discrepancy between early measurements and calculations. The [sup 252]Cf-source-driven noise analysis measurements confirmed the validity of the calculational methods. In addition to providing the neutron multiplication factor from point-kinetics interpretation of the data, these measurements also provided the auto-power and cross-power spectral densities as a function of frequency, which can be calculated directly with recently developed Monte Carlo methods and thus could also be used to validate calculational methods and cross-section sets.},
doi = {10.13182/NT93-3},
url = {https://www.osti.gov/biblio/5982020}, journal = {Nuclear Technology; (United States)},
issn = {0029-5450},
number = ,
volume = 103:3,
place = {United States},
year = {1993},
month = {9}
}