JENDL-5 Benchmarking for Advanced Test Reactor for Preparing Burnup Analysis Using Isotopic Data From HTGR Type Fuel Irradiation Tests

Abstract Japan Atomic Energy Agency (JAEA) has been developing a methodology for nuclide generation-depletion and decay heat evaluations for High Temperature Gas-cooled Reactors (HTGRs). We are planning to perform validation of the evaluation method with isotopic composition data obtained from HTGR type fuel irradiation tests (AGR tests) performed at the Idaho National Laboratory. As a first step of this plan, preliminary validation of a core calculation model of the Advanced Test Reactor (ATR) is performed with a continuous-energy Monte Carlo code MVP-3. We made the calculation model with the latest nuclear data library in Japan called by JENDL-5. We also calculated effective multiplication factors and relative power densities for the ATR calculation model. As a result of comparison with measured values reported in the IRPhE handbook, the JENDL-5 and the calculation model built with MVP-3 showed a good calculation accuracy within experimental error range in the effective multiplication factor and ±8.8% in the relative power density distribution. The results will help us to perform our planned validation of our nuclide generation-depletion and decay heat evaluation methodology with the AGR test data.