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Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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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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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.
Shao-Rong Wu, Klaus Rehme
Nuclear Technology | Volume 89 | Number 1 | January 1990 | Pages 103-115
Technical Paper | Heat Transfer and Fluid Flow | doi.org/10.13182/NT90-A34362
Articles are hosted by Taylor and Francis Online.
Measurements of the mean velocity, wall shear stresses, and turbulent Reynolds stresses were performed in wall subchannels of two rod bundles. The rod bundle of four parallel rods was arranged symmetrically in a rectangular channel. The pitch-to-diameter ratio was 1.148, and the wall-to-diameter ratios were 1.045 and 1.074, respectively. The Reynolds numbers in these investigations were 6.11 × 104 and 7.07 × 104, respectively. The experimental results demonstrate once more that the structure of turbulence in rod bundles differs greatly from the structure in circular tubes. Especially in the narrow gaps between the rods and channel walls, there are increased levels of turbulence intensities in both the axial and azimuthal directions and, hence, of the kinetic energy of turbulence, caused by a strong turbulent momentum transport through the gaps. In comparison with the previous investigations in these geometries, however, arranged asymmetrically in the rectangular channels, the momentum transport between the subchannels across the gap between the rods is negligible. The comparison between the experimental wall shear stress distributions and those computed by the VELASCO code shows strong deviations, especially in the gap regions between the rods and channel walls. More sophisticated analytical tools than presently available are required to predict turbulent flow through rod bundles with sufficient accuracy.