Developing a Science-Based Predictive Simulation Capability for the Design and Analysis of Advanced Nuclear Fuel Concepts Operating in a Virtual Reactor Environment

Nuclear power can increase profitability, reliability, and safety by developing and deploying advanced nuclear fuels. These nuclear fuel concepts aim to increase fuel structural integrity and decrease fuel temperatures, resulting in increased profitability due to longer fuel cycle life and uprating reactor power. DOE-NE advanced modeling and simulation tools exist to support the nuclear industry in achieving these lofty goals by predicting fuel behavior in a virtual reactor environment for existing licensed nuclear fuel and advanced nuclear fuel concepts, such as Westinghouse's ADOPT fuel and the many HALEU fuel configurations for Advanced Reactor Technologies. The nuclear industry can leverage DOE's science-based predictive simulation capability for effectively analyzing the evolution of nuclear fuel concepts through high burnup regimes, thus providing insight into which fuel concepts have the most promising fuel performance before investing in time-consuming and expensive fuel experiments. A science-based predictive simulation approach will minimize the experimental program and accelerate the acceptance and deployment of the fuel. Under Topic C58-29a. Advanced Modeling and Simulation, Sawtooth Simulation LLC proposes building a Numerical Test Bed for Fuels (NTBF). The NTBF will analyze advanced and existing fuel concepts for both the current fleet of Light Water Reactors (LWRs) and various Advanced Reactor Technologies (ARTs) in a virtual nuclear power plant (NPP) environment. The NTBF will use many of the required advanced modeling and simulation tools (https://neams.inl.gov/code-descriptions/) that the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program provides. NTBF will have high-resolution reactor physics coupled with multiscale fuel performance and thermomechanics to give the nuclear power community a science-based predictive capability for effectively analyzing existing and advanced fuel concepts, mainly where little to no experimental data exists. Phase I tasks will focus on developing an advanced simulator that couples high-resolution reactor physics with fuel performance and thermal fluids. Fuel model improvements are necessary due to insufficient experimental data for UO2 fuel at greater than 5% U-235 enrichment. Phase I tasks include implementing fuel models that predict fuel behavior at 6.5% U-235 enrichment for extended fuel life and reactor uprating and models for incorporating Cr2O3 doped fuel properties to reduce fracturing and lowering centerline fuel temperatures. Phase II development of the numerical test bed for fuels is motivated by the need for experimental data on advanced nuclear fuels, including HALEU. Phase II tasks involve the development of mechanistic models for cladding oxidation and creep deformation for longer-term/higher burnup applications of both zirconium-based and coated zirconium alloys to the mechanistic-based extension of the material degradation models for uranium oxide nuclear fuel, as well as chromia-doped nuclear fuel.