Applicability of JENDL-5 to Tihange Unit 2 Reactor Core Analysis

The fifth version of the Japanese Evaluated Nuclear Data Library (JENDL-5) was released in December 2021. It is essential to validate JENDL-5 using the reactor core analysis data of light water reactors and to evaluate the performance of JENDL-5 in comparison with other major nuclear data libraries, namely, JENDL-4.0, ENDF/B-VIII.0, and ENDF/B-VII.1. In this paper, reactor core analyses of Tihange-2, which is a three-loop 900-MW(electric) Framatome pressurized water reactor, were performed using CASMO5/SIMULATE5. The results indicated that the radial power distributions were accurately simulated using JENDL-5, but discrepancies in the critical boron concentration during cycle burnups were observed. The main cause of these discrepancies was found to be low reactivity caused by the ²³⁹Pu reaction cross section in JENDL-5. Accordingly, further validation and code updates are expected in applying the library to core analyses of light water reactors.