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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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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.
Wayne Strasser, Robert Kacinski, Daniel Wilson, Victor Petrov, Annalisa Manera
Nuclear Technology | Volume 210 | Number 7 | July 2024 | Pages 1185-1211
Research Article | doi.org/10.1080/00295450.2023.2238156
Articles are hosted by Taylor and Francis Online.
Hybrid Reynolds-Averaged Navier-Stokes–Large Eddy Simulation was used to reveal detailed flow information and timescales in an isothermal reactor cavity cooling system plenum four-jet configuration. Plenum asymmetry and nonuniformity work together to cause premature jet merging. Bulk stirring in the plenum causes lateral jet vortex shedding, strong jet-jet interactions, swirl, and premature confluence. Two dominant transient modes exist: a jet flow timescale and then a plenum circulation timescale that is nearly three orders of magnitude larger. A primary consequence is that frequencies far less than the presumed 10 Hz threshold for thermal striping are pervasive. A second result is that scale-resolved computational fluid dynamics (CFD) models (as well as experimental rigs) need hundreds of seconds of statistically stationary flow time (tens of thousands of jet timescales) to produce stationary time averages. Fluid typically arrives at positions on the laser sheet in less time than it spends at those positions fluctuating in the streamwise and lateral directions. Also, a previously undocumented, but experimentally confirmed, vortex trap was identified via CFD. Finally, two-point velocity correlation analyses demonstrated a few dozen strong correlations across positions on the laser sheet. Expected close-proximity correlations emerged, but others across larger spaces also were connected. Most of these correlated at timescales close to that of the jet.