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Division Spotlight
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.
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.
Rui Hu, Mujid S. Kazimi
Nuclear Technology | Volume 176 | Number 1 | October 2011 | Pages 57-71
Technical Paper | Second Seminar on Accelerated Testing of Materials in Spent Nuclear Fuel and High-Level Waste Storage Systems / Fission Reactors | doi.org/10.13182/NT11-A12542
Articles are hosted by Taylor and Francis Online.
To help achieve the necessary natural circulation flow, a fairly long chimney is installed in a natural circulation boiling water reactor (BWR) like the ESBWR. In such systems, hot water near the chimney exit could flash, thus leading to thermal-hydraulic instability during low-pressure start-up. A BWR stability analysis code in the frequency domain, named the Flashing-Induced STability Analysis for BWR (FISTAB), was developed in this work to address the issue of flashing-induced instability. The FISTAB code was benchmarked against the experimental results from the SIRIUS-N facility at the Central Research Institute of Electric Power Industry in Japan. Both stationary and perturbation results agreed well with the experimental observations.The proposed ESBWR start-up procedure under natural convection conditions was examined by the FISTAB code. It was confirmed that the examined operating points along the ESBWR start-up trajectory from TRACG simulation would be stable. Furthermore, to avoid the instability resulting from the transition from single-phase natural circulation to two-phase circulation, a simple criterion was proposed for the natural convection BWR start-up when the steam dome pressure is still low.