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DOE OSTI · 2569568

Advanced System Thermal Fluids Solver Development for SAM

Zou, Ling [Argonne National Laboratory (ANL), Argonne, IL (United States)]·Hu, Rui [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000237712920)
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Abstract

This work summarizes a feasibility study on testing numerical algorithms that are suitable and efficient for advanced system analysis code development under the mutli-physics framework, MOOSE. The key is the implementation of a high-order one-dimensional staggered-grid finite volume method (SG-FVM), and its direct interaction with the linear/nonlinear solver, PETSc. Leveraging the existing capabilities of the SAM code, significant code coverages were established in the finite volume method code. This in turn allows for a suite of test problems with different problem sizes and levels of complexity to be used to quantify the performance improvement of the finite volume method code. As evidently shown in this study, the implemented SG-FVM demonstrated superior performance improvement against a direct finite element method implementation through MOOSE for the wide range of selected problems. On two computer systems, the speedup was observed to be significant, with at least one order of magnitude of solving time reduction. In addition, for a complex reactor model, transient simulation was performed using the finite volume method code, the results of which agree very well with the reference results from the finite element method code. Overall, this study demonstrates a successful feasibility study on the proposed numerical algorithms and software structure to support advanced system analysis tool development. In this work, short-term priority development and testing items were identified, and long-term code adoption and integration plans were made for the eventual deployment of the finite volume method in the SAM code.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS97 MATHEMATICS AND COMPUTING

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Zou, Ling [Argonne National Laboratory (ANL), Argonne, IL (United States)], Hu, Rui [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000237712920). 2025-06-01. Advanced System Thermal Fluids Solver Development for SAM. https://doi.org/10.2172/2569568

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