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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.
Wolfgang Suttrop, Albrecht Herrmann, François Ryter, Jörg Karl Stober
Fusion Science and Technology | Volume 44 | Number 3 | November 2003 | Pages 636-649
Technical Paper | ASDEX Upgrade | doi.org/10.13182/FST03-A404
Articles are hosted by Taylor and Francis Online.
Studies in ASDEX Upgrade of the phenomenology and scaling of the H-mode transition, of edge-localized modes (ELMs), and characterization of the H-mode edge transport barrier carried out in various experimental campaigns between 1996 and 2001 are described. The H-mode transition is recognized by formation of a radial electrical field at the plasma boundary, which in ASDEX Upgrade is detected by an associated increase of the neutral particle charge exchange flux from ripple trapped particles. A scaling for the critical local edge temperature for the H-mode transition threshold is found. Similarity experiments with ASDEX Upgrade and Joint European Torus plasmas for the H-mode transition indicate that the H-mode transition can be obtained at the same values of dimensionless parameters *, *, and at the plasma edge, indicating that the threshold scaling is normally not dominated by atomic physics processes. Energy losses due to ELMs are examined. Different types of ELMs can be obtained, depending on plasma edge temperature and magnetics configuration. An interesting regime is the type II ELMy H-mode for configurations near double null, where the peak heat flux to the target is much reduced compared to large type I ELMs. High-resolution Thomson scattering measurements show that the edge transport barrier width in ASDEX Upgrade shows only weak variations, while the pedestal top electron pressure and pressure gradient strongly depend on the plasma current, or value of Bt/q95.
