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Modernizing I&C for operations and maintenance, one phase at a time
The two reactors at Dominion Energy’s Surry plant are among the oldest in the U.S. nuclear fleet. Yet when the plant celebrated its 50th anniversary in 2023, staff could raise a toast to the future. Surry was one of the first plants to file a subsequent license renewal (SLR) application, and in May 2021, it became official: the plant was licensed to operate for a full 80 years, extending its reactors’ lifespans into 2052 and 2053.
A. V. Melnikov, A. Alonso, E. Ascasíbar, R. Balbin, A. A. Chmyga, Yu. N. Dnestrovskij, L. G. Eliseev, T. Estrada, J. M. Fontdecaba, C. Fuentes, J. Guasp, J. Herranz, C. Hidalgo, A. D. Komarov, A. S. Kozachek, L. I. Krupnik, M. Liniers, S. E. Lysenko, K. J. McCarthy, M. A. Ochando, I. Pastor, J. L. De Pablos, M. A. Pedrosa, S. V. Perfilov, S. Ya. Petrov, V. I. Tereshin, TJ-II Team
Fusion Science and Technology | Volume 51 | Number 1 | January 2007 | Pages 31-37
Technical Paper | Stellarators | doi.org/10.13182/FST07-A1284
Articles are hosted by Taylor and Francis Online.
The heavy ion beam probe diagnostic is used in the TJ-II stellarator to study directly the plasma electric potential with good spatial (up to 1 cm) and temporal (up to 2 s) resolution. Singly charged heavy ions, Cs+, with energies of up to 125 keV are used to probe the plasma column from the edge to the core. Both electron cyclotron resonance heating (ECRH) and neutral beam injection (NBI)-heated plasmas (PECRH = 200 to 400 kW, PNBI = 200 to 400 kW, ENBI = 28 keV) have been studied.Low-density ECRH [[over bar]n = (0.5 to 1.1) × 1019 m-3] plasmas in TJ-II are characterized by positive plasma potential on the order of 1000 to 400 V. A negative electric potential appears at the edge when the line-averaged density exceeds 0.5 × 1019 m-3. Further density rises are accompanied by a decrease in the core plasma potential, which becomes fully negative for plasma densities [over bar]n 1.5 × 1019 m-3. The NBI plasmas are characterized by a negative electric potential across the whole plasma cross section from the core to the edge. In this case, the absolute value of the central potential is on the order of -500 V. These results show a clear link between plasma potential and density in the TJ-II stellarator.