Nuclear reactors, whether Light Water Reactors (LWRs) or liquid metal cooled fast reactors, are complex machines requiring detailed design in complex multiphysics scenarios. Modeling and simulation (M&S) are key elements in the design and advanced safety modeling of nuclear reactors. In this project, Illinois Rocstar plans to extend our NEMoSys meshing package to support autonomous adaptive mesh refinement and solution verification to better serve the needs of the nuclear energy M&S community.
In the past, reactor M&S was often performed with one-dimensional models that resorted to lumped parameter methods, homogenization, and empirical correlations. The advent of high performance computing (HPC), computational fluid dynamics (CFD), and high fidelity neutronics methods led to the formation of advanced modeling and simulation tools, such as the SHARP (Simulation for High-efficiency Advanced Reactor Prototyping) framework and Nek5000, that facilitated the crucial task of reactor design and optimization by providing understanding of complex physical phenomena.
Further, physical insights about the processes affecting such parameters as the degree of cross-assembly mixing, distribution of coolant flow in the core, and the magnitude of the pressure drop through the assembly are now attainable that were previously accessible only through experiment. Critical to the use of the results of these simulations are appropriate V&V of the codes, models, and solutions. While all stages of V&V require significant effort, the grid manipulations required during solution verification are often manual and arduous. This project, through upgrade and modification to Illinois Rocstar’s NEMoSys product, targets the automation of the solution verification step of Verification and Validation (V&V).
