Analysis of in-vessel accident progression in VVER1000 NPP during SBO accident with external reactor vessel cooling method

Doan Manh Long1, Nguyen Van Thai2, Tran Chi Thanh3
1 Nuclear Training Center, 140 Nguyen Tuan, Thanh Xuan, Hanoi
2 Department of Nuclear Engineering and Environmental Physics, School of Engineering Physics, Hanoi University of Science and Technology, 01 Dai Co Viet, Hai Ba Trung, Hanoi
3 Viet Nam Atomic Energy Institute, 59 Ly Thuong Kiet, Hoan Kiem, Hanoi

Main Article Content


In this study, the MELCOR v1.8.6 code was utilized to perform an analysis of the in-vessel accident progression in VVER1000 reactor during the Station Black-Out (SBO) accident with and without external reactor vessel cooling (ERVC) strategy. The analysis presented the predictions of the main phenomena during the accident such as failure of fuel cladding, collapse of lower core support plate, relocation of core debris to lower plenum and mass of debris components in lower plenum, and provided comparisons between two cases in term of main parameters such as integrity time of reactor and structure components of molten pool. These parameters are very important inputs for further research on the application of external vessel cooling strategy for VVER1000 reactor.

Article Details


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