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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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Hash Hashemian: Visionary leadership
As Dr. Hashem M. “Hash” Hashemian prepares to step into his term as President of the American Nuclear Society, he is clear that he wants to make the most of this unique moment.
A groundswell in public approval of nuclear is finding a home in growing governmental support that is backed by a tailwind of technological innovation. “Now is a good time to be in nuclear,” Hashemian said, as he explained the criticality of this moment and what he hoped to accomplish as president.
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.