b'Validation of BISON Swelling Model for Metallic FuelPrincipal Investigator: Christopher Matthews, INLTeam Members/ Collaborators: Cetin Unal, INLCollaboration betweenT he BISON fuel performancereactors. With FCCI as the primary code is well underway to beinglimiting factor of metallic fuels, modelers from differentextended to model zirconiumenhancements in understanding and backgrounds and acrossbased metallic fuel. The challengesmodeling of the key phenomena DOE programs has ledpresented by the advanced U-Zr andinvolved in FCCI can help bolster the to strides in multi-scaleU-Pu-Zr fuel types have resultedeconomic viability of metallic fuel modeling capability andin a coupled thermo-mechanical-through extending the fuel lifetime. enhanced robustnessdiffusion simulation required toSimultaneously, the coupled nature of of metallic fuel BISONdescribe historical observations, asnuclear fuel requires the implementa-simulations. well as predict future performance.tion of many fundamental models in Advances in fundamental models suchorder to provide a baseline capability as swelling, fission gas release, andfor advanced concepts and off-zirconium diffusion will help providenormal behavior.the necessary foundation for advancedDue to the sparse availability of models such as cladding creep failuresmodern data, historical EBR-II and fuel-cladding chemical interactiondata is used as a primary source of (FCCI). Benchmark comparisons toinformation for model formulation past postirradiation examinationsand comparison. Previous codes have (PIE)are utilized to assess modelbeen limited to heavily empirical performance, with advancedmodels due to limited resources, calibration techniques playing a roleunderstanding, and data. By leveraging when data is sparse or unavailable. many of the capabilities within BISON, Project Description: advanced models that capture complex The objective of this research isbehavior can be implemented in a to provide a code that can predictviable way. In addition, on going work behavior of zirconium based metallicwithin the Advanced Fuels Campaign fuel for use in future advanced Gen(AFC) has helped bolster the limited IV commercial or test reactors suchdata set with new irradiations and as the Versatile Test Reactor (VTR)higher fidelity data collection. Modern currently under development. Thecomputational tools such as Bayesian favorable thermal conductivity andcalibration have been implemented proven safety record of metallicto help bridge over limited data. fuel experienced during operationIn general, metallic fuel modeling of experimental breeder reactorin BISON aims to create a tool that (EBR)-II lends U-Zr and U-Pu-Zris predictive in order to provide fuel naturally to the requirements ofconfidence for core designers in the enhanced safety in next generationsafe, reliable, and efficient use of metallic nuclear fuel.226 2019|AFC ACCOMPLISHMENTS'