Assessment of a Physics-Based Model of Microcracking and Microstructural Evolution for Fission Gas Release and Swelling in Ceramic Nuclear Fuels with Multiple Data Sets

We assess the enhanced version of the Simple Integrated Fission Gas Release and Swelling (SIFGRSX) model for fission gas swelling and release, recently developed in the fuel performance code BISON, with simulations of the Risø-AN3, Risø-AN4, and Risø-II3 light water reactor fuel rod irradiation experiments from the Organisation for Economic Co-operation and Development/Nuclear Energy Agency’s International Fuel Performance Experiments database, as well as the IFA-677.1 and IFA-716.1 tests of the Halden Reactor Project.The wealth of data corresponding to a broad range of operating conditions and initial grain sizes provides important insights that enable a rigorous assessment of the model for microcracking, microstructural evolution, and fission gas behavior beyond that of our earlier work in which we first proposed the model. Through this comprehensive assessment, we recalibrate the SIFGRSX model and identify a small handful of model ingredients that must be adjusted to properly describe the experimental measurements. Our findings provide meaningful improvements to the SIFGRSX model that will be useful for large-scale simulations of nuclear fuel performance.