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DOE OSTI · 3015152

$χ$-$MeRA$: Computationally efficient adaptive mesh refinement of Monte Carlo mesh based tallies

Stolte, Kristin Nichole·Tsvetkov, Pavel V.
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Abstract

Here, the reactor physics community is always focused on reducing the computational time and memory required for simulations. $χ$-$MeRA$, which stands for flux-based-($χ$)-Mesh tally Refinement Adaptively, was built to reduce the computational time and memory required to solve the neutronics side of a multiphysics problem when compared to traditional methods for mesh based tallies in Monte Carlo (MC) simulations. $χ$-$MeRA$ couples a MC code with an adaptive mesh refinement (AMR) algorithm to take advantage of the accuracy of a MC code and the efficiency of an AMR algorithm. Also developed within $χ$-$MeRA$ was a set of metrics to assess the effects of the refinement on various parameters in the simulation space. For a plutonium sphere, $χ$-$MeRA$ shows a reduction in memory usage and computation time when compared to a fully refined mesh by a factor of 14.7 and 6.7, respectively. When compared to an unstructured mesh, improvement of 1.3 and 4.8 was achieved for memory usage and computation time. The development of $χ$-$MeRA$ helps solve the neutronics side of a multiphysics problem in a faster, more computationally efficient manner than traditional methods, and the final mesh created contains accurate results that can be passed onto the next physics code.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSAdaptive mesh refinementMCNPMesh based talliesMonte Carlo methodsχ-MeRA

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Stolte, Kristin Nichole, Tsvetkov, Pavel V.. 2022-12-12. $χ$-$MeRA$: Computationally efficient adaptive mesh refinement of Monte Carlo mesh based tallies. https://doi.org/10.1016/j.anucene.2022.109617

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