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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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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Fusion Science and Technology
Latest News
ARPA-E announces $40 million to develop transmutation technologies for UNF
The Department of Energy’s Advanced Research Projects Agency–Energy (ARPA-E) announced $40 million in funding to develop cutting-edge technologies to enable the transmutation of used nuclear fuel into less-radioactive substances. According to ARPA-E, the new initiative addresses one of the agency’s core goals as outlined by Congress: to provide transformative solutions to improve the management, cleanup, and disposal of radioactive waste and spent nuclear fuel.
Kazuyoshi Hada, Kazunobu Nagasaki, Kai Masuda, Shinji Kobayashi, Shunsuke Ide, Akihiko Isayama, Ken Kajiwara
Fusion Science and Technology | Volume 67 | Number 4 | May 2015 | Pages 693-704
Technical Paper | doi.org/10.13182/FST14-811
Articles are hosted by Taylor and Francis Online.
By using a one-dimensional model, we analyze plasma start-up assisted by second-harmonic extraordinary-mode electron cyclotron (EC) resonance heating (ECRH). The model leads to energy transport equations for electrons and ions, particle transport equations for electrons and hydrogen atoms, and a toroidal current equation. These equations are solved for a cylindrically symmetrical plasma; that is, a torus straightened to a cylinder with a circular cross section and on-axis ECRH power absorption. The calculation indicates that ECRH has a threshold power for plasma start-up in JT-60SA. For example, approximately 1 MW of ECRH power is required for plasma start-up for an initial hydrogen atom density nH(t=0) = 3.0 × 1018 m-3, an error field Berr = 1 mT, carbon and oxygen impurity fractions nc/ne = no/ne = 0.1%, and an EC beam radius of approximately 5 cm. This estimated ECRH power is less than the planned power and increases sublinearly with the initial hydrogen atom density. The threshold power depends weakly on the error field and carbon impurity concentration. This is especially prominent for plasma start-up with a low initial hydrogen atom density. This result implies that suppressing the error field and carbon impurity density is helpful for reliable plasma start-up.