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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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.
Chiaki Kino, Yoshihiro Morita, Masao Chaki (The Inst of Applied Energy)
Proceedings | Advances in Thermal Hydraulics 2018 | Orlando, FL, November 11-15, 2018 | Pages 201-211
Reactor core isolation cooling system (RCIC) is designed to operate using saturated steam extracted from a main steam line. On the other hand, RCIC in Unit-2 of Fukushima Daiichi Nuclear Power Plant was activated before the tsunami hit and continued to operate under two phase flow conditions during the accident. When RCIC continuously operates without control by electric power, reactor water level would reach the main steam line resulting in turbine efficiency degradation and subsequent RCIC stop. The mechanism for RCIC of Unit-2 to have continuously operated under such two phase flow conditions is still unclear. Currently, a project is progressing to understand the true operating limitations of RCIC system under beyond design basis event. The Institute of Applied Energy is developing the new RCIC system model for the SAMPSON code in the project. The present paper proposes a trial model for RCIC system under two phase flow conditions. The model takes the effect of quality and pressure on turbine efficiency into consideration. SAMPSON calculation based on the model could reproduce qualitatively RPV pressure behavior of Fukushima Daiichi Unit-2 accident. However there are many uncertainties, such as water temperature of S/P, isentropic efficiency, and so on, so the model will be improved based on experiment and CFD results planned in the project.