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Title: Sensitivity and Uncertainty Analysis of Plutonium and Cesium Isotopes in Modeling of BR3 Reactor Spent Fuel

Abstract

Nuclear forensics has a broad task to characterize recovered nuclear or radiological material and interpret the results of investigation. One approach to isotopic characterization of nuclear material obtained from a reactor is to chemically separate and perform isotopic measurements on the sample and verify the results with modeling of the sample history, for example, operation of a nuclear reactor. The major actinide plutonium and fission product cesium are commonly measured signatures of the fuel history in a reactor core. This study investigates the uncertainty of the plutonium and cesium isotope ratios of a fuel rod discharged from a research pressurized water reactor when the location of the sample is not known a priori. A sensitivity analysis showed overpredicted values for the 240Pu/ 239Pu ratio toward the axial center of the rod and revealed a lower probability of the rod of interest (ROI) being on the periphery of the assembly. The uncertainty analysis found the relative errors due to only the rod position and boron concentration to be 17% to 36% and 7% to 15% for the 240Pu/ 239Pu and 137Cs/ 135Cs ratios, respectively. Lastly, this study provides a method for uncertainty quantification of isotope concentrations due to the location ofmore » the ROI. Similar analyses can be performed to verify future chemical and isotopic analyses.« less

Authors:
 [1];  [1];  [2];  [2]
  1. Georgia Inst. of Technology, Atlanta, GA (United States)
  2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1411672
Report Number(s):
LLNL-JRNL-681885
Journal ID: ISSN 0029-5450
Grant/Contract Number:
AC52-07NA27344
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nuclear Technology
Additional Journal Information:
Journal Volume: 197; Journal Issue: 1; Journal ID: ISSN 0029-5450
Publisher:
Taylor & Francis - formerly American Nuclear Society (ANS)
Country of Publication:
United States
Language:
English
Subject:
98 NUCLEAR DISARMAMENT, SAFEGUARDS AND PHYSICAL PROTECTION; 11 NUCLEAR FUEL CYCLE AND RUEL MATERIALS; 21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; forensics; isotope; uncertainty

Citation Formats

Conant, Andrew, Erickson, Anna, Robel, Martin, and Isselhardt, Brett. Sensitivity and Uncertainty Analysis of Plutonium and Cesium Isotopes in Modeling of BR3 Reactor Spent Fuel. United States: N. p., 2017. Web. doi:10.13182/NT16-88.
Conant, Andrew, Erickson, Anna, Robel, Martin, & Isselhardt, Brett. Sensitivity and Uncertainty Analysis of Plutonium and Cesium Isotopes in Modeling of BR3 Reactor Spent Fuel. United States. doi:10.13182/NT16-88.
Conant, Andrew, Erickson, Anna, Robel, Martin, and Isselhardt, Brett. Fri . "Sensitivity and Uncertainty Analysis of Plutonium and Cesium Isotopes in Modeling of BR3 Reactor Spent Fuel". United States. doi:10.13182/NT16-88. https://www.osti.gov/servlets/purl/1411672.
@article{osti_1411672,
title = {Sensitivity and Uncertainty Analysis of Plutonium and Cesium Isotopes in Modeling of BR3 Reactor Spent Fuel},
author = {Conant, Andrew and Erickson, Anna and Robel, Martin and Isselhardt, Brett},
abstractNote = {Nuclear forensics has a broad task to characterize recovered nuclear or radiological material and interpret the results of investigation. One approach to isotopic characterization of nuclear material obtained from a reactor is to chemically separate and perform isotopic measurements on the sample and verify the results with modeling of the sample history, for example, operation of a nuclear reactor. The major actinide plutonium and fission product cesium are commonly measured signatures of the fuel history in a reactor core. This study investigates the uncertainty of the plutonium and cesium isotope ratios of a fuel rod discharged from a research pressurized water reactor when the location of the sample is not known a priori. A sensitivity analysis showed overpredicted values for the 240Pu/239Pu ratio toward the axial center of the rod and revealed a lower probability of the rod of interest (ROI) being on the periphery of the assembly. The uncertainty analysis found the relative errors due to only the rod position and boron concentration to be 17% to 36% and 7% to 15% for the 240Pu/239Pu and 137Cs/135Cs ratios, respectively. Lastly, this study provides a method for uncertainty quantification of isotope concentrations due to the location of the ROI. Similar analyses can be performed to verify future chemical and isotopic analyses.},
doi = {10.13182/NT16-88},
journal = {Nuclear Technology},
number = 1,
volume = 197,
place = {United States},
year = {Fri Feb 03 00:00:00 EST 2017},
month = {Fri Feb 03 00:00:00 EST 2017}
}

Journal Article:
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  • A comprehensive sensitivity and uncertainty analysis was performed on a 1200-MW(thermal) minor actinide burner designed for a low burnup reactivity swing, negative Doppler constant, and low sodium void worth. Sensitivities of the performance parameters were generated using depletion perturbation methods for the constrained closed fuel cycle of the reactor. The uncertainty analysis was performed using the sensitivity and covariance data taken from ENDF/B-V and other published sources. The uncertainty analysis of a liquid-metal reactor for burning minor actinides has shown that uncertainties in the nuclear data of several key minor actinide isotopes can introduce large uncertainties in the predicted performancemore » of the core. The relative uncertainties in the burnup swing, Doppler constant, and void worth were conservatively estimated to be 220, 120, and 59%, respectively. An analysis was performed to prioritize the minor actinide reactions for reducing the uncertainties.« less
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