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DOE OSTI · 2417762

Data reduction in deterministic neutron transport calculations using machine learning

Whewell, Ben·McClarren, Ryan G.
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Abstract

Neutron cross section matrices for fission and scattering data are required for each material, temperature, and enrichment level to calculate the neutron transport equation accurately. Here, this information can be a limiting factor when using the multigroup discrete ordinates (S N ) method when the number of energy groups is large. Machine Learning (ML) can be used to replace the need for the cross section matrices by reproducing the function that maps the scalar flux to the scattering and fission sources. Through the use of autoencoders and Deep Jointly-Informed Neural Networks (DJINN), the data storage requirements are reduced by 94% of the original data for a 618 group problem. This is accomplished while preserving the scalar flux, maintaining generality, and decreasing wall clock times.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSAutoencodersData reductionDeep learningMachine learningNeutron transport equationNuclear Science & Technology

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Whewell, Ben, McClarren, Ryan G.. 2022-06-20. Data reduction in deterministic neutron transport calculations using machine learning. https://doi.org/10.1016/j.anucene.2022.109276

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