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Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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State lawmakers across the country push for more nuclear
From lifting moratoriums to launching studies to labeling it as clean, state lawmakers are exploring ways to give nuclear energy a boost in 2025. Here’s a look at some of the pronuclear legislation under review.
Prasad Vegendla, Rui Hu, Aleksandr Obabko, Haomin Yuan (ANL), Richard Schultz (Idaho State Univ), Yassin Hassan (Texas A&M)
Proceedings | Advances in Thermal Hydraulics 2018 | Orlando, FL, November 11-15, 2018 | Pages 1169-1180
In High Temperature Gas Reactors (HTGR), gas flow patterns are very complex and reduced models (1D or 2D) may be too simplified to predict accurate reactor performance. 3D Computational Fluid Dynamics (CFD) models can help provide the detailed information needed to optimize the reactor thermal performance. The main objective of this work is to verify and validate the CFD models with data for a 1/16th scaled Very High Temperature Reactor (VHTR) measured at Texas A&M University. The upper plenum is one of the main components in a VHTR where the hot and cold fluids mix with each other to determine the fluid temperature.
In this paper, jet flow characteristics are investigated in two different upper plenum configurations; (i) single coolant channel and (ii) multiple (five) coolant channel. First, CFD models are verified with two different codes, Nek5000 and STAR-CCM+, for the single coolant channel configuration. The predicted jet velocities are identical in both codes with a marginal deviation due to differences in turbulence modeling. Second, the STAR-CCM+ Reynolds Stress Model (RSM) is validated with a multiple coolant channel configuration. Good agreement between simulated results and measured data is obtained for jet peak velocities. Also, the predicted flow asymmetry is similar to experimental data. In contrast, significant deviations are observed in the off side peak velocities due to the assumption of a constant inlet mass flow rate.
