Modeling radionuclide release of TRISO bearing fuel compacts during post-irradiation annealing tests

Abstract This article presents calculated radionuclide release fractions from TRISO fuel during post-irradiation annealing and comparison with AGR-1 irradiated TRISO compacts using the BISON fuel performance code. The BISON code was found to produce good agreement in an analytical comparison and with legacy German TRISO compact irradiation data. However, the recommended IAEA fission product diffusion coefficients did not produce good agreement with the 2014 AGR-1 data (Demkowicz et al., 2015). Thus, the diffusion coefficients prefactors and activation energies were modified to obtain best agreement with the recent AGR data. Future work involves investigating the release behavior of silver from silicon carbide and implementing methods to provide predictive capability for the silver release behavior.