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The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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Fusion Science and Technology
Latest News
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has since been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that Unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. local time on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
Osamu Mitarai, Akira Hirose, Harvey M. Skarsgard
Fusion Science and Technology | Volume 16 | Number 2 | September 1989 | Pages 197-210
Technical Paper | Plasma Engineering | doi.org/10.13182/FST89-A29148
Articles are hosted by Taylor and Francis Online.
The concept of a generalized ignition contour map, showing , nτE, and T, is extended to the realistic case of a plasma with temperature and density profiles in order to study access to ignition in a tokamak reactor ( is the average total auxiliary heating power density). The “generalized” saddle point, which corresponds to the minimum height of , is found to lie between the Lawson and ignition conditions. If the height of the operation path with Goldston L-mode scaling is higher than the generalized saddle point, a reactor can reach ignition with this scaling for the case with no confinement degradation effect due to alpha-particle heating. In this sense, the saddle point given in a general form is a new criterion for reaching ignition. Peaking the profiles for the plasma temperature and density can lower the height of the generalized saddle point and help a reactor to reach ignition. With this in mind, we can judge whether next-generation tokamaks, such as Compact Ignition Tokamak, Tokamak Ignition/Burn Experimental Reactor, Next European Torus, Fusion Experimental Reactor, International Tokamak Reactor, and AC Tokamak Reactor, can reach ignition with realistic profile parameters and an L-mode scaling law. We can also obtain the required confinement enhancement factor with respect to L-mode scaling for reaching ignition. The confinement degradation effects on the operation path due to alpha heating are also considered.