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DOE OSTI · 2406839

Investigating Similarity Differences for Light-Water-Moderated and Polyethylene-Moderated Systems [Slides]

Greene, T. M.·Marshall, W. J.
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Abstract

Validation efforts revealed noticeable differences in c k for light-water and polyethylene moderated systems when compared to experimental systems. Although 1 H-H 2 O and 1 H-poly use some of the same cross section and identical covariance data, the treatment of TSLs in SCALE lead to no contribution to c k between polyethylene application and benchmark experiment. When H 2 O contribution is removed the difference in c k appears to come from 239 Pu chi. Sensitivity profiles and data-induced uncertainty confirm that the polyethylene application more closely resembles the benchmark experiment. Interrogation techniques were used to observe how TSLs and nuclide IDs affect c k . Specific differences between similar systems can be accounted for and examined to help understand differences in similarity (c k ) between systems

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSAnalytical MethodsNuclear Criticality Safety Program (NCSP)SCALE

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Greene, T. M., Marshall, W. J.. 2023-10-05. Investigating Similarity Differences for Light-Water-Moderated and Polyethylene-Moderated Systems [Slides]. https://doi.org/10.2172/2406839

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