Production-class High Fidelity Nuclear Reactor Simulation Leveraging Advanced Computing Libraries

Industry core simulators that are the cornerstone of reactor analysis for the operating fleet of nuclear plants are used in numerous application areas, including core and fuel design, safety licensing, core monitoring, and training. Currently licensed industry codes, while capable of reconstructing fuel rod detail for local power, suffer from several geometrical and physics simplifications that require an additional margin in calculated operational and safety parameters. This excess conservatism results in more restrictive thermal, chemistry, and reactivity operating limits that ultimately result in higher fuel and operating costs for the reactor fleet. In addition, new fuel products characterized by higher burnup, high enrichment, and advanced clad and fuel forms are hampered by existing industry simulation methods. Advances in modeling and simulation for nuclear reactors and high-performance computing have provided unprecedented accuracy in predicting core and fuel rod behavior. These advances are well-positioned to identify and utilize today’s excess conservatism to improve the efficiency of the current and future reactor operating fleet and decrease costs. Across the national fleet of 93 reactors, eliminating conservatism in a handful of application areas through advanced modeling and simulation is estimated to have a value of over $300 million per year. This includes providing industry solutions characterized by highly resolved multi-physics coupling and high accuracy in areas such as fuel crud risk management, fuel performance during operational maneuvering, bounding licensing analyses such as reactivity insertion accidents, and plant lifetime extension. This project seeks to address a significant barrier to adopting advanced modeling and simulation for the nuclear industry: the high computational resource required, on the order of tens of hundreds of processors, which does not lend itself to production computing in many use cases. The project will leverage software libraries that facilitate the porting of existing software for use on advanced computing hardware. Extending the existing high-fidelity models to leverage advanced computing hardware will decrease the overall computational burden of reactor simulations, facilitating easier deployment to the nuclear industry. In phase 1, several of the critical components of the reactor simulator will be rewritten to leverage a range of advanced computing hardware as micro-applications. Phase 2 will integrate the best practices learned from these micro-applications and deploy a production-class reactor core simulator leveraging state-of-the-art computer hardware. This software would then be applied throughout the nuclear industry to improve the safe and efficient operation of existing and new carbon-free electricity from nuclear power.