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DOE OSTI · 1886339

Using the Criticality Accident Alarm System modeling capabilities in SCALE [Slides]

Dupont, Mathieu
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Abstract

The following is a summary of advice for CAAS modeling in SCALE. Refer to the SCALE Criticality Safety and Radiation Shielding training slides or to the SCALE manual for exact syntax. Use a mesh for the fission source that is the most adequate for the problem to solve (coarse/fine). Don’t spend unnecessary resources; simplify the model if it does not impact the final results of interest. Be careful to deactivate secondary fissions in MAVRIC or the calculation may never end. Check that k eff and $\overline{\upsilon}$ calculated results are logical. Between KENO and MAVRIC, cross section libraries, materials, geometry, and mesh grid can be the same or different. Iterative calculations are usually complex problems that need variance reduction. It will be hard to find the best solving parameters in the first attempt; expert judgement is needed. Check each step separately. Use Fulcrum to visualize fission source, mesh source, and spatial/energy distributions to find potential errors or impactful imprecisions.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS97 MATHEMATICS AND COMPUTINGcriticality accident alarm systemhealth physics research reactorinformation preservation and disseminationKENOMAVRICNuclear Criticality Safety Program (NCSP)

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Dupont, Mathieu. 2022-04-27. Using the Criticality Accident Alarm System modeling capabilities in SCALE [Slides]. https://doi.org/10.2172/1886339

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