ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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Nuclear Science and Engineering
September 2024
Nuclear Technology
August 2024
Fusion Science and Technology
Latest News
Taking shape: Fusion energy ecosystems built with public-private partnerships
It’s possible to describe fusion in simple terms: heat and squeeze small atoms to get abundant clean energy. But there’s nothing simple about getting fusion ready for the grid.
Private developers, national lab and university researchers, suppliers, and end users working toward that goal are developing a range of complex technologies to reach fusion temperatures and pressures, confounded by science and technology gaps linked to plasma behavior; materials, diagnostics, and electronics for extreme environments; fuel cycle sustainability; and economics.
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.