Mesoscale modeling for restructuring and fragmentation in the dark zone of high burnup UO 2
This report summarizes the mesoscale modeling conducted in fiscal year 2025 under the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program, focusing on the microstructural evolution and restructuring in high burnup UO 2 nuclear fuel and its impact on fuel fragmentation. We developed a pioneering phase-field model to simulate restructuring behavior across different regions of […]
Thermal-Mechanic Modeling of Fusion Components Using The MOOSE Framework
With fusion energy rapidly developing, there is a great need for an open source tool that can rapidly model different fusion tokamak designs. The open-source codes Multiphysics Object Oriented Simulation Environment (MOOSE), Tritium Migration Analysis Program Version 8 (TMAP8) , and Fusion ENergy Integrated Multiphysi-X (FENIX) are being used to demonstrate thermal-mechanic modeling of fusion […]
Meso-scale modeling of UO2 nuclear fuel to high burnup
To improve the economics of light water reactors for commercial nuclear energy generation, utility operators are seeking to obtain regulatory approval to run UO2 fuel to higher levels of burnup. One potential impediment to obtaining this approval is the phenomenon of fuel fragmentation, relocation, and dispersal (FFRD). FFRD can result when fuel experiences a rapid […]
Enabling BWR fuel rod analysis in the BISON fuel performance code
Nuclear fuel vendors around the world are pursuing approaches to sustain the existing nuclear reactor fleet con- sisting primarily of pressurized-water reactors (PWRs) and boiling-water reactors (BWRs). To support the industry’s efforts, advanced modeling and simulation tools need to be capable of analyzing both legacy reactor concepts. BWR fuel rods are significantly different than those […]
MOOSE-based Tritium Migration Analysis Program, Version 8 (TMAP8) for advanced open-source tritium transport and fuel cycle modeling
Tritium management is critical for the safety, sustainability, and economics of fusion energy systems, and advanced and reliable modeling tools help accelerate the development of tritium technologies. This paper presents the Tritium Migration Analysis Program, Version 8 (TMAP8), an open-source, MOOSE-based application developed to provide state-of-the-art tritium transport and fuel cycle modeling capabilities. TMAP8 aims […]
Unpacking model inadequacy: The quantification of silver release from TRISO fuel by considering empirical and mechanistic approaches
Increasing adoption of the proposed tristructural isotropic (TRISO) particle fuel for both advanced and existing reactors makes it critical to assess and address any uncertainties and inadequacies of TRISO fission product release models. Model inadequacy stems from simplifications made to the computational model when compared to the experiments. The modeling and simulation efforts conducted using […]
Multi-Scale Modeling of the Evolution of Structure and Properties in Materials for Nuclear Energy Applications
Nuclear energy is an important component of an overall strategy to address climate change. Idaho National Laboratory (INL) is the U.S. Department of Energy’s primary facility for research and development in nuclear science and technology for energy generation, supporting the improvement and life extension of the existing reactor fleet and the development and licensing of […]
Development of mechanistic, microstructure-informed BISON models for fission product-induced failure mechanisms in advanced nuclear fuels
The US continues to prioritize commercial deployment of advanced reactors—particularly those utilizing U-Zr metallic and TRISO particle fuels. Fission product-induced failure mechanisms for these systems include fuel–cladding chemical interaction in metallic fuel rods, which threatens cladding integrity, and Pd penetration in TRISO particles, which degrades SiC layer properties. Empirical models can be applied within the […]
Deployment of BISON models of fuel restructuring at high burnup and related fission gas behavior in UO2
This milestone report details the advancements made in fiscal year 2024 under the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program to improve the modeling of fission gas behavior in high burnup UO2 nuclear fuel in the BISON fuel performance code. As nuclear fuel is pushed to higher burnups, significant microstructural changes occur within the […]
Phase-field modeling for restructuring in the dark zone of high burnup UO2
This report summarizes the mesoscale modeling work performed in fiscal year 2024 under the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program to capture the microstructural evolution and restructuring observed in the dark regions of high burnup UO2 nuclear fuel. This is the first attempt to realistically simulate the restructuring behavior observed in different region […]