Investigation of DPA in the reactor pressure vessel of VVER-1000/V320

Nguyen Huu Tiep1, Pham Nhu Viet Ha1, Nguyen Minh Tuan2
1 Institute for Nuclear Science and Technology, Vietnam Atomic Energy Institute. 179 Hoang Quoc Viet Street, Cau Giay, Ha Noi, Viet Nam
2 Dalat Nuclear Research Institute, Vietnam Atomic Energy Institute. 01 Nguyen Tu Luc, Da Lat, Lam Dong, Viet Nam

Main Article Content


The most important ageing effect on the reactor pressure vessel (RPV) is radiation embrittlement, which is mainly caused by fast neutrons during operation lifetime of nuclear reactors. The aim of this study was to investigate the DPA (displacement per atom) rate, an important parameter describing radiation damage to the RPV, and identify the position of the maximum DPA rate in the RPV of the VVER-1000/V320 reactor using the Monte Carlo code MCNP5. To reduce statistical errors in the MCNP5 simulation, the weight window technique was applied to non-repeated structures outside the reactor core. The results showed the distribution of the DPA rate in the RPV and the maximum DPA rate was found to be at the first millimeters of the RPV. Consequently, these calculations could be useful for assessment of radiation damage to the RPV of VVER reactors.

Article Details


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