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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.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Securing the advanced reactor fleet
Physical protection accounts for a significant portion of a nuclear power plant’s operational costs. As the U.S. moves toward smaller and safer advanced reactors, similar protection strategies could prove cost prohibitive. For tomorrow’s small modular reactors and microreactors, security costs must remain appropriate to the size of the reactor for economical operation.
Jiyun Zhao, Pradip Saha, Mujid S. Kazimi
Nuclear Technology | Volume 158 | Number 2 | May 2007 | Pages 158-173
Technical Paper | Nuclear Reactor Thermal Hydraulics | doi.org/10.13182/NT07-A3833
Articles are hosted by Taylor and Francis Online.
The drastic change of fluid density in the reactor core of a supercritical water-cooled reactor (SCWR) gives rise to a concern about density-wave stability. Using a single-channel thermal-hydraulic model, stability boundary maps for the U.S. reference SCWR design have been constructed for both steady state and sliding pressure startup conditions.The supercritical water flow in the reactor core has been simulated using a three-region model: a heavy fluid with constant density, a mixture of heavy fluid and light fluid similar to a homogeneous-equilibrium two-phase mixture, and a light fluid, which behaves like an ideal gas or superheated steam. Two important nondimensional numbers, namely, a pseudosubcooling number Npsub and an expansion number Nexp, have been identified for the supercritical region. The stability map in the supercritical region is then plotted in the plane made of these two numbers. The U.S. reference SCWR design operates in a stable region with a large margin. Sensitivity studies produced results consistent with the findings of the earlier research done for the subcritical two-phase flow.During the sliding pressure startup of the SCWR, a two-phase steam-water mixture at subcritical pressure will appear in the reactor core. A nonhomogeneous (e.g., drift-flux) nonequilibrium two-phase flow model was applied. The characteristic equation was numerically integrated, and stability boundary maps were plotted on the traditional subcooling number versus phase change number (or Zuber number) plane. These maps have been used to develop a sliding pressure SCWR startup strategy avoiding thermal-hydraulic flow instabilities.