Computational modeling of graphite degradation in molten salt reactors: Infiltration and wear effects

[vprithiv]

Model Description

A coupled multiphysics finite element model was developed to evaluate the structural integrity of graphite components in molten salt reactor (MSR) environments, focusing on two degradation mechanisms: molten salt infiltration and surface wear. Implemented within the MOOSE framework, the model simulates thermomechanical behavior under steady-state conditions, incorporating volumetric heating from infiltrated salt and radiation-induced effects such as dimensional change and creep. For infiltration studies, a representative geometry from the Molten Salt Reactor Experiment (MSRE) was used, and rare-event simulations using the Parallel Subset Simulation (PSS) method were employed to quantify failure probabilities under uncertainty. Some infiltration simulations used the Grizzly code to include irradiation effects. For wear analysis, a generic fluoride-cooled high-temperature reactor (gFHR) reflector block was modeled using Grizzly, with idealized surface defects such as pits and grooves to assess stress distributions.

Project description

This project was funded by the U.S. Nuclear Regulatory Commission under Task Order Number 31310022F0034. This model was developed by Veerappan Prithivirajan and Benjamin Spencer.

Impact

This work provided advanced modeling and simulation strategies for assessing the performance of graphite components in MSRs. The simulation approaches, including the coupled multiphysics framework and rare-event simulation techniques, offer a robust foundation for evaluating structural integrity, considering various effects such as thermal loading, infiltration, radiation, and wear. These tools are adaptable to various geometries and graphite grades, and support future investigations aimed at optimizing material selection, component design, and long-term reactor safety.

closes #669

[GiudGiud]

@vprithiv this is failing precheck due to whitespaces and end-of-file linebreaks.

You should install the moose plugin in VSCode to get the formatting right automatically. If not then yuou will need to fix each file manually with ctrl shift P + search for the commands to delete the trailing white spaces, and adding the EOF linebreaks manually

[moosebuild]

Job VTB Documentation, step Sync Docs on f40653b wanted to post the following:

View the site here

This comment will be updated on new commits.

[GiudGiud]

Going to upload LFS files in a separate PR Test failures are expected until then

[GiudGiud]

Thanks for contributing your two models @vprithiv!