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DOE OSTI · 1809983

Hierarchical Data Format for Nuclear Data Sensitivities

McDonnell, Jordan·Wieselquist, William
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Abstract

The SCALE code system includes capabilities for sensitivity and uncertainty (S/U) analysis as part of its TSUNAMI code suite. The sensitivity of a quantity of interest (for example, an application’s $k_{eff}$) to nuclear data is stored as a profile in a text-based file, which is known as a sensitivity data file (SDF). The sensitivity profile can be used to calculate uncertainties, correlation coefficients, and similarity indices. One of the goals of the present work was to seek general performance improvements in the TSUNAMI code suite, starting with the TSUNAMI-IP code for calculating similarity indices. Through profiling, it was found that reading the text-based sensitivity files was a performance bottleneck in the TSUNAMI-IP code. In a typical TSUNAMI-IP calculation, an application might be compared to thousands of benchmarks, thus requiring the reading of thousands of SDFs. Reading of binary-based data is generally faster than reading text-based data. Hierarchical Data Format 5 (HDF5) is a binary-based format that also benefits from being portable, and it can be inspected with nonproprietary tools. This paper describes an HDF5-based file format that has been introduced for SDFs.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS97 MATHEMATICS AND COMPUTINGHierarchical Data Format 5 (HDF5)Nuclear Criticality Safety Program (NCSP)Nuclear DataSCALESensitivity Data File (SDF)TSUNAMI-IP

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McDonnell, Jordan, Wieselquist, William. 2021-06-15. Hierarchical Data Format for Nuclear Data Sensitivities. https://doi.org/10.13182/t124-35210

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