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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
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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.
J. L. Kloosterman, V. V. Golovko, H. van Dam, T. H. J. J. van der Hagen
Nuclear Science and Engineering | Volume 139 | Number 2 | October 2001 | Pages 118-137
Technical Paper | doi.org/10.13182/NSE01-A2227
Articles are hosted by Taylor and Francis Online.
A new type of nuclear reactor is presented that consists of a graphite-walled tube partly filled with TRISO-coated fuel particles. Helium is used as a coolant that flows from bottom to top through the tube, thereby fluidizing the particle bed. Only when the coolant flow is large enough does the reactor become critical because of the surrounding graphite that moderates and reflects the neutrons.The fuel particle designed for this reactor is strongly undermoderated and has a temperature coefficient of reactivity that is sufficiently negative. The outer diameter is 1 mm with a fuel kernel diameter of 0.26 mm. The fuel enrichment (16.7%) and the core inventory (120 kg of uranium) inherently limit the maximum power to 16 MW(thermal).A lumped-temperature point-kinetics model has been made that describes the fluidization of the particle bed, coupled to the thermal hydraulics and the neutronics of the core. The model has been linearized around the stationary solution, and the transfer function from coolant mass flow rate perturbations to reactor power fluctuations has been calculated. From a root-locus analysis, the reactor operation is shown to be stable with respect to small variations of the coolant mass flow rate around the stationary operation points.Transient analyses with the nonlinear reactor model show that for the three transients considered (a step in the coolant mass flow rate, a decrease of the coolant inlet temperature, and a loss of heat sink), the fuel temperature remains well below 1600°C. Recommendations are made for further research.