2024-03-28T20:51:37Z
https://nagoya.repo.nii.ac.jp/oai
oai:nagoya.repo.nii.ac.jp:02003808
2023-03-03T01:18:36Z
320:321:322
Application of dynamic mode decomposition to Rossi-α method in a critical state using file-by-file moving block bootstrap method
Endo, Tomohiro
Nishioka, Fuga
Yamamoto, Akio
Watanabe, Kenichi
Pyeon, Cheol Ho
Prompt neutron decay constant
Rossi-α method
critical experiment
dynamic mode decomposition
bootstrap method
KUCA
validation
JENDL
FRENDY
MCNP
Prompt neutron decay constant α in a critical state is useful information to validate the numerically predicted ratio of the point kinetics parameters βeff/ℓ, where βeff and ℓ are the effective delayed neutron fraction and prompt neutron lifetime, respectively. To directly measure α in a target critical system, this study proposes the application of the dynamic mode decomposition (DMD) to the reactor noise analysis based on the Rossi-α method. The DMD-based Rossi-α method enables us to robustly estimate the fundamental mode component of α from the Rossi-α histograms measured using multiple neutron detectors. Furthermore, the file-by-file moving block bootstrap method is newly proposed for the statistical uncertainty quantification of α to prevent huge memory usage when the neutron count rate is high and/or the total measurement time is long. A critical experiment has been conducted at Kyoto University Critical Assembly to demonstrate the proposed method. As a result, the proposed method can uniquely determine the α value of which the statistical uncertainty is smallest. By utilizing this experimental result of α, numerical results of βeff/ℓ ratio using the continuous energy Monte Carlo code MCNP6.2 with recent nuclear data libraries, which are processed by the nuclear data processing code FRENDY, are validated.
Published online: 27 Feb 2022
journal article
Taylor & Francis
2022-02-27
application/pdf
Journal of Nuclear Science and Technology
9
59
1117
1126
0022-3131
https://nagoya.repo.nii.ac.jp/record/2003808/files/JNST59_9_pp1117-1126_2022.pdf
eng
https://doi.org/10.1080/00223131.2022.2030260
This is an Accepted Manuscript of an article published by Taylor & Francis Group in Journal of Nuclear Science and Technology on 27/02/2022, available online: http://www.tandfonline.com/10.1080/00223131.2022.2030260.