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Getting back to yes: A local perspective on decommissioning, restart, and responsibility
For 45 years, Duane Arnold Energy Center operated in Linn County, Ia., near the town of Palo and just northwest of Cedar Rapids. The facility, owned by NextEra Energy, was the only nuclear power plant in the state.
In August 2020, a historic derecho swept across eastern Iowa with winds approaching 140 miles per hour. Damage to the plant’s cooling towers accelerated a shutdown that had already been planned, and the facility entered decommissioning soon after, with its fuel removed in October of that year. Iowa’s only nuclear plant had gone off line.
Today the national energy landscape looks very different than it did just six short years ago. Electricity demand is rising rapidly as data centers, artificial intelligence infrastructure, advanced manufacturing, and electrification expand across the country. Reliable, carbon-free baseload power has become increasingly valuable. In that context, Linn County has approved the rezoning necessary to support the recommissioning and restart of Duane Arnold and is actively supporting NextEra’s efforts to secure the remaining state and federal approvals.
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.
