Nuclear data sensitivity and uncertainty for the Canadian supercritical water-cooled reactor

Highlights: • An idealisation of the Canadian SCWR is modelled with the code set, TSUNAMI. • The SCWR model shows a high sensitivity to contributions from the isotopes H-2, Pu-239, and Th-232. • Isotopes of Zr make a large contribution to SCWR modeling uncertainty. • Results of this study demonstrate the need for improved nuclear data evaluations for SCWR modeling. - Abstract: Accurate and complete nuclear data are a fundamental requirement for any nuclear reactor model. Present nuclear data evaluations have been tested and validated against experiments that cover operating conditions and materials that are typical of conventional reactors (e.g. thermal light and heavy water moderated reactors, and some fast reactors). The Canadian supercritical water-cooled reactor (SCWR) is an advanced reactor concept for which, like all advanced GEN-IV reactor concepts, operating conditions and materials differ significantly from conventional reactors. Consequently, current nuclear data evaluations may not be suitable for modeling the Canadian SCWR, either due to assumptions or gaps in the evaluations or gaps in the experimental data on which the evaluations are based. In this paper, a simplified model of an SCWR fuel channel with fresh fuel is analyzed in order to determine the sensitivities and uncertainties of the model to nuclear data. The results are used to determine which isotopes and which reactions make the largest contributions to the sensitivity and uncertainties in key reactor physics parameters such as the neutron multiplication factor, k, and various lattice reactivity coefficients