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Division Spotlight
Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
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.