Development of importance measures reflecting the risk triplet in dynamic probabilistic risk assessment; The Concept and measures of risk importance

Narukawa, Takafumi*; Takata, Takashi*; Zheng, X.; Tamaki, Hitoshi; Shibamoto, Yasuteru; Maruyama, Yu; Takada, Tsuyoshi

Journal of Nuclear Engineering (Internet), 6(4), p.49_1 - 49_14, 2025/12

https://doi.org/10.3390/jne6040049

Development of importance measures reflecting the risk triplet in dynamic probabilistic risk assessment; A Case study using MELCOR and RAPID

Zheng, X.; Tamaki, Hitoshi; Shibamoto, Yasuteru; Maruyama, Yu; Takada, Tsuyoshi; Narukawa, Takafumi*; Takata, Takashi*

Journal of Nuclear Engineering (Internet), 6(3), p.21_1 - 21_18, 2025/06

https://doi.org/10.3390/jne6030021

Development of risk importance measures for dynamic PRA based on risk triplet, 2; Trial measurement of risk importance through dynamic level 2 PRA with RAPID

Zheng, X.; Tamaki, Hitoshi; Shibamoto, Yasuteru; Maruyama, Yu; Takada, Tsuyoshi; Narukawa, Takafumi*; Takata, Takashi*

Proceedings of Probabilistic Safety Assessment and Management & Asian Symposium on Risk Assessment and Management (PSAM17 & ASRAM2024) (Internet), 10 Pages, 2024/10

The Effect of a cyclic bending load on the bending resistance of ballooned, ruptured, and oxidized Zircaloy-4 cladding

Li, F.; Narukawa, Takafumi; Udagawa, Yutaka

Journal of Nuclear Science and Technology, 61(8), p.1036 - 1047, 2024/08

https://doi.org/10.1080/00223131.2023.2293100

Oxidation and embrittlement behavior of FeCrAl-ODS cladding tube under loss-of-coolant accident conditions

Narukawa, Takafumi; Kondo, Keietsu; Fujimura, Yuki; Kakiuchi, Kazuo; Udagawa, Yutaka; Nemoto, Yoshiyuki

Journal of Nuclear Materials, 587, p.154736_1 - 154736_8, 2023/12

https://doi.org/10.1016/j.jnucmat.2023.154736

Behavior of FeCrAl-ODS cladding tube under loss-of-coolant accident conditions

Narukawa, Takafumi; Kondo, Keietsu; Fujimura, Yuki; Kakiuchi, Kazuo; Udagawa, Yutaka; Nemoto, Yoshiyuki

Journal of Nuclear Materials, 582, p.154467_1 - 154467_12, 2023/08

https://doi.org/10.1016/j.jnucmat.2023.154467

Toward a more reliable evaluation of fuel fracture during LOCA; Development of uncertainty quantification methodology and evaluation of the effect of fuel burnup extension

Narukawa, Takafumi

Nihon Genshiryoku Gakkai-Shi ATOMO, 63(11), p.780 - 785, 2021/11

https://doi.org/10.3327/jaesjb.63.11_780

no abstracts in English

Technical basis of ECCS acceptance criteria for light-water reactors and applicability to high burnup fuel

Nagase, Fumihisa; Narukawa, Takafumi; Amaya, Masaki

JAEA-Review 2020-076, 129 Pages, 2021/03

JAEA-Review-2020-076.pdf:3.9MB

Each light-water reactor (LWR) is equipped with the Emergency Core Cooling System (ECCS) to maintain the coolability of the reactor core and to suppress the release of radioactive fission products to the environment even in a loss-of-coolant accident (LOCA) caused by breaks in the reactor coolant pressure boundary. The acceptance criteria for ECCS have been established in order to evaluate the ECCS performance and confirm the sufficient safety margin in the evaluation. The limits defined in the criteria were determined in 1975 and reviewed based on state-of-the-art knowledge in 1981. Though the fuel burnup extension and necessary improvements of cladding materials and fuel design have been conducted, the criteria have not been reviewed since then. Meanwhile, much technical knowledge has been accumulated regarding the behavior of high-burnup fuel during LOCAs and the applicability of the criteria to the high-burnup fuel. This report provides a comprehensive review of the history and technical bases of the current criteria and summarizes state-of-the-art technical findings regarding the fuel behavior during LOCAs. The applicability of the current criteria to the high-burnup fuel is also discussed.

Fracture limit of high-burnup advanced fuel cladding tubes under loss-of-coolant accident conditions

Narukawa, Takafumi; Amaya, Masaki

Journal of Nuclear Science and Technology, 57(1), p.68 - 78, 2020/01

https://doi.org/10.1080/00223131.2019.1659873

Oxidation behavior of high-burnup advanced fuel cladding tubes in high-temperature steam

Narukawa, Takafumi; Amaya, Masaki

Journal of Nuclear Science and Technology, 56(7), p.650 - 660, 2019/07

https://doi.org/10.1080/00223131.2019.1613268