Nuclear data uncertainty propagation to selected BR2 safety parameters

Nuclear data are used as input parameters to the neutron transport codes used for reactor calculations at the BR2 reactor. Since these data contain uncertainties, it implies that these uncertainties would ultimately lead to uncertainties in simulation outputs. In this work, the Total Monte Carlo approach was applied for propagating uncertainties due to nuclear data for a selected number of isotopes of importance to the BR2 representative HEU and LEU cores, to the keff and the neutron flux. It was observed that the uncertainty in the keff for the combined variation of U235 and U238 nuclear data as well as the H-1 and Al-27 were relatively large with significant contributions coming from H-1 nuclear data for both cores.
customer-defined neutronic conditions can be achieved. This in-core structure contains instrumentation for on-line monitoring of neutronic and thermal-hydraulic conditions during irradiation. Two irradiations are planned for the MUSTANG-R apparatus: full-size Design Demonstration Elements (DDEs) for both Massachusetts Institute of Technology Reactor (MITR) and the National Bureau of Standards Reactor (NBSR), denoted by MITR DDE and NBSR DDE.
Furthermore, the design foresees to irradiate other elements such as a Generic Test Assembly (GTA).