An extension of the validation of SCALE (SAS2H) isotopic predictions for PWR spent fuel

Abstract

IThis report has been reproduced directly from the best available copy.Availabte to DOE and DOE contractors from the Office of Scientific and Technical Information, P.0.Box 62, Oak Ridge, TN 37831; prices available from (423) 576-8401, FTS 626-8401Available to the public from the National Technical Information Service, U.S. Department of Commerce, 5285 Port Royal Rd., Springfield, VA 22161 I This report was prepared a an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The view and opinions of authors expressed herein do not necessarily state or reflect those of the UnitedStatesGovemment or any agency thereof. DISCLAIMERPortions of this document may be illegible in electronic image products. Images are produced from the best available original document. In addition, an approach to determine biases and uncertainties between calculated and measured isotopic concentrations is discussed, together with a method to statistically combine these terms to obtain a conservative estimate of spent fuel isotopic concentrations. Results are presented based on the combination of measured-to-calculated ratios for earlier work and the current analyses.The results described herein represent an extension to a new reactor design not included in the earlier work, and spent fuel samples with enrichment as high as 3.9 wt % u5U. Results for the current work are found to be, for the most part, consistent with the findings of the earlier work. This consistency was observed for results obtained from each of two different crosssection libraries and suggests that the estimated biases determined for each of the isotopes in the earlier work are reasonably good estimates, as the additional measurement/calculated ratios resulting from the current work tend to confirm these estimates. vii ACKNOWLEDGMENTS

Benchmark of SCALE (SAS2H) isotopic predictions of depletion analyses for San Onofre PWR MOX fuel

“…Any fuel-depletion code used for this purpose must be evaluated to determine how the accuracies of the spent fuel content computations compare with those of the more common low-enriched-uranium (LEU)-fueled light-water reactors (LWRs). Validation studies have been conducted for the SCALE code system fuel-depletion analyses (applying SAS2H 2 ) of spent fuel for both pressurized-water reactors 3 (PWRs) and boiling-water reactors 4 (BWRs). During the operation of these reactors, the plutonium gradually increases in the fuel that initially contained only uranium oxide.…”

Used Fuel Storage Monitoring Using Helium-4 Scintillation Fast Neutron Detectors and Neutron Spectral Analysis

“…Uncertainties in decay constants, cross sections, and fission spectra lead to further uncertainties in the final neutron flux and neutron energy spectrum measured in the tally results. Evaluating the propagation and impact of these uncertainties is the subject of ongoing research [34] [35].…”

Isotope correlation technique for Pu mass analysis of PWR UO2 spent fuel rods

“…As much destructive analysis (DA) data as possible for segments taken from a pressurized water reactor (PWR) UO 2 spent fuel rod were collected from publicly available data sources (i.e., research papers, reports, and the OECD/NEA database) [7][8][9][19][20][21][22][23][24][25]. DA data was collected only for PWR UO 2 spent nuclear fuel.…”