A Preliminary Study on BP/CP Uncertainty Analysis of Wolsong CANDU 6 Reactors based upon RFSP-IST Fine Mesh Core Model

Abstract

A preliminary study has been conducted to help estimate BP/CP uncertainty of Wolsong CANDU 6 reactors by using the WIMS/DRAGON/RFSP-IST code system. The study is focused on the effects of RFSP-IST core modeling practices, especially, in context of laying out mesh spacings associated with the structural materials in the core. The conceptual approach to figure out the effects of mesh spacing layouts associated with the structural materials is supported by the newly updated code system representing the state-of-the-art CANDU reactor physics theory and methodologies, especially, the DRAGON-IST generated incremental cross sections. The application of RFSP-IST fine mesh core model has been exercised to Wolsong Unit 2 core tracking simulations for about one year period of reactor operations. The results so obtained clearly indicate that the improved validation practices and methodology presented here could be qualified to be incorporated into the entire package of BP/CP uncertainty analysis methodologies in order to enhance the quality and reliability of error estimates related to the various topics, e.g., such as, off-line flux mapping errors.