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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
Rei Kimura, Yuki Nakai, Satoshi Wada
Nuclear Science and Engineering | Volume 195 | Number 12 | December 2021 | Pages 1279-1290
Technical Paper | doi.org/10.1080/00295639.2021.1908081
Articles are hosted by Taylor and Francis Online.
A novel ex-core-detector–based core power reconstruction method is presented. The method uses power correlations between fuel regions and can be applied to a real-time small reactor core monitoring system especially for the detection of abnormal behavior. The use of ex-core detectors reduces the installation and maintenance costs of small modular reactors (SMRs) compared to conventional in-core detectors. To construct the power distribution with ex-core-detector count rates, it is necessary to account for the scattering and absorption reactions of neutrons within the core that make it difficult to extract information directly from the central core region. In the proposed method, detector responses and power correlations are preevaluated and revised by mathematical transformation. Monte Carlo simulations using the realistic SMR core design MoveluXTM demonstrated that the present method is capable of reconstructing the core power distributions within an average error of 10% using the count rates of the ex-core detectors. Also, the reconstruction successfully identified the position of abnormal power peaks in the central core region and an unbalanced power distribution.