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DOE OSTI · 1762135

Initial full core SMR simulations with NekRS

Merzari, Elia·Fang, Jun·Shaver, Dillon R.·Lan, Yu-Hsiang·Min, Misun·Fischer, Paul F.·Rahaman, Ronald Omah·Romano, Paul K.
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Abstract

This document describes the completion of a recent milestone of the ExaSMR program concerning "Full core simulations". The ExaSMR project is developing tools for coupling Monte Carlo (MC) radiation transport solvers to a computational fluid dynamics (CFD) solver. Work is based on the Shift MC, OpenMC MC, and Nek5000/NekRS CFD codes. As part of this milestone, a novel set of pin-resolved CFD full-core simulations have been performed for the first time. These simulations represent a significant increase in capability in what is now possible with CFD on pre-Exascale systems. The simulations have been performed with the spectral element solvers NekRS on the supercomputer Summit. Multiple simulations campaigns have been conducted: (1) LES simulations in bare bundle, (2) RANS simulations in bare bundles, (3) RANS simulations with momentum sources and (4) Conjugate heat transfer calculations.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS

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Merzari, Elia, Fang, Jun, Shaver, Dillon R., Lan, Yu-Hsiang, Min, Misun, Fischer, Paul F., Rahaman, Ronald Omah, Romano, Paul K.. 2020-10-01. Initial full core SMR simulations with NekRS. https://doi.org/10.2172/1762135

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