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DOE OSTI · 3014272

MPACT Testing and Benchmarking Results

Godfrey, Andrew T.
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Abstract

This document provides detailed reactivity and fission rate distribution results for MPACT for the Core Physics Benchmark Progression Problems 1-5, including comparisons to initial startup data from Watts Bar Nuclear Unit 1. Also included are computer requirements and runtimes for each type of problem and feedback for issues encountered during the testing. Testing for the benchmark problems that do not require thermal-hydraulic feedback has been very successful. Testing for the coupled problems (6 and 7) is still ongoing and will be documented in a future revision or separate document. A few issues have been identified needing more research/investigation before all of these problems have ideal solutions. These items are included in the Section 8 near the end of this document. MPACT has successfully solved all of the zero power core physics progression problems. The computer resources required and runtimes were all acceptable, though faster cases would be preferable considering there was no thermal-hydraulic feedback. MPACT converged very reliably for all 3D problems, expect in a few isolated studies where very thin axial planes were purposely created to attempt to quantify the errors in the control rod tip homogenization model. Despite the issues listed in Section 8, the accuracy of MPACT compared to the reference solution is considered to be very good.

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21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS22 GENERAL STUDIES OF NUCLEAR REACTORS73 NUCLEAR PHYSICS AND RADIATION PHYSICS97 MATHEMATICS AND COMPUTING

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Godfrey, Andrew T.. 2014-03-31. MPACT Testing and Benchmarking Results. https://doi.org/10.2172/3014272

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