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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Yasunori Yamanaka, Shinya Mizokami, Manabu Watanabe, Takeshi Honda
Nuclear Technology | Volume 186 | Number 2 | May 2014 | Pages 263-279
Technical Paper | Reactor Safety | doi.org/10.13182/NT13-46
Articles are hosted by Taylor and Francis Online.
Because of the Great East Japan Earthquake, and the resulting tsunami, which occurred on March 11, 2011, a serious accident occurred in Units 1, 2, and 3 of the Fukushima Daiichi nuclear power station. Since the accidents, data from interviews with operators and on-site surveys have been continuously compiled. Based on the data, a plant-state analysis has been conducted using the severe accident analysis code MAAP (Modular Accident Analysis Program). Parallel to the MAAP analysis, the responses of the plant to site operations, such as water injection, are analyzed, and core conditions are comprehensively evaluated. According to the evaluation, in Unit 1, it is presumed that almost no fuel was left at the original position; it was molten and moved downward. The fuel likely damaged the reactor pressure vessel (RPV), and it is assumed that most of it had dropped to the primary containment vessel (PCV) pedestal. In Units 2 and 3, it is presumed that some of the fuel was left at the original position and the rest dropped to the bottom of the RPV or to the PCV pedestal. In the MAAP analysis, the behavior of the plants before core melt is reproduced. However, RPV damage of Units 2 and 3 does not occur in the MAAP analysis, which is contrary to the observed facts. This shows that the analysis capability of the current MAAP code is limited. Therefore, by developing severe accident analysis codes to achieve higher levels of accuracy and by evaluating the plant responses to site operation, we will continue to obtain a clear picture of the states inside the reactor so that fuel debris can be removed.