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DOE OSTI · 1836106

M3 milestone: Advanced contact 2021

Yushu, Dewen·Martin Recuero, Antonio·Schwen, Daniel·Lindsay, Alexander D·Spencer, Benjamin W
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Abstract

This report describes advanced contact approaches and implementations in FY21 for use in emerging reactors with geometries that differ from LWR/EBR-II cylindrical fuel. Contact remains a challenging and crucially important component of our modeling toolkit. While significant improvements have been made through mortar and automatic differentiation, we explored advanced approaches (i.e., dual mortar) that yields better conditioned systems and will improve the robustness and performance of BISON contact problems. This effort is relevant to emerging reactor types, such as micro reactors and the corresponding complex and numerous contact surfaces. In this report, improvements of the mortar-based contact formulation are described. Benchmark problems and BISON assessment cases are included to demonstrate the improvements and advantages that are brought by the recent capability. Remaining issues are discussed and corresponding development plans are outlined.

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11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS97 MATHEMATICS AND COMPUTINGBISONContactDocumentationFinite Element MethodMOOSE

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Yushu, Dewen, Martin Recuero, Antonio, Schwen, Daniel, Lindsay, Alexander D, Spencer, Benjamin W. 2021-09-30. M3 milestone: Advanced contact 2021. https://www.osti.gov/biblio/1836106

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