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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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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Latest News
U.K., Japan to extend decommissioning partnership
The U.K.’s Sellafield Ltd. and Japan’s Tokyo Electric Power Company have pledge to continue to work together for up to an additional 10 years, extending a cooperative agreement begun in 2014 following the 2011 tsunami that resulted in the irreparable damage of TEPCO’s Fukushima Daiichi plant.
Byeong-Il Jang, Moo Hwan Kim, Gyoodong Jeun
Nuclear Technology | Volume 177 | Number 2 | February 2012 | Pages 203-216
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT12-A13366
Articles are hosted by Taylor and Francis Online.
Research regarding small- and medium-sized nuclear reactors (SMRs) has increased because of multipurpose applications and increased safety. According to this tendency, a new conceptual nuclear reactor, the Regional Energy rX-10MWt (REX-10), is being designed. REX-10 adopts a way to remove heat by natural circulation and integrates the primary systems within a reactor pressure vessel. To evaluate the steady-state and transient behavior of natural circulation in REX-10, a NAtural Circulation TEst Reactor (NACTER) is designed using the scaling law. The ratio of the height and core power are 1/3 and 1/500, respectively.This research can be divided into three parts - a steady-state experiment, a transient experiment, and MARS (Multidimensional Analysis for Research Safety) code analysis. To investigate the natural circulation characteristics under the steady-state conditions, two parameters were chosen and various experiments were conducted. As a result of the steady-state experiment, we show that the most important parameter that affects the natural circulation behavior is the heater power. In addition, we carried out a transient experiment. The results of the transient experiment are that the NACTER facility is well controlled and guarantees safety in abrupt changes in experimental conditions. Finally, MARS code simulations were conducted. The MARS code results show good agreement with the experimental results.
