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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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Latest News
Katy Huff reflects on her time in the Office of Nuclear Energy
After three years in the Department of Energy, including two as assistant secretary of the Office of Nuclear Energy, Katy Huff stepped down in May to return to the world of academia as a professor at the University of Illinois–Urbana-Champaign.
Among her many accomplishments while serving as NE-1, Huff pushed for energy security—both at home and abroad, in places like war-torn Ukraine—and for the development of additional advanced and traditional nuclear plants, the potential restart of shuttered nuclear facilities, and a better funding stream for college nuclear programs.
T. Sehmer, K. Lackner, E. Strumberger, E. Fable, O. Kardaun, P. McCarthy, ASDEX Upgrade Team
Fusion Science and Technology | Volume 70 | Number 1 | July 2016 | Pages 73-82
Technical Paper | doi.org/10.13182/FST15-175
Articles are hosted by Taylor and Francis Online.
Modern tokamaks, operating with elongated plasmas, are unstable against vertical displacement. In the presence of conducting walls, this instability assumes the characteristics of a resistive wall mode (RWM), amenable to feedback stabilization. On ASDEX Upgrade (AUG), estimates of the growth rates, entering into the definition of safe operating regimes and into feedback parameter settings, were so far based on a rigid displacement (RD) model. However, for highly triangular plasmas this model was found to predict growth rates that were too small. A code package originally developed for general ideal magnetohydrodynamic (MHD) RWMs (NEMEC/CAS3D/STARWALL) and also capable of handling three-dimensional passive stabilizing loops (PSLs) was therefore applied to the n = 0 case for a large data sample of possible AUG equilibria. The comparison with the previously used rigid vertical displacement model showed that the latter gives a consistently lower limit to the growth rates for typical AUG parameters. A statistical analysis of the RD results brings out the stabilizing effect of triangularity. This stabilizing effect disappears, however, if generalized displacements are taken into account, like in the full MHD resistive wall model. The mode acquires a strong m = 2 component, which allows it also to elude partly the stabilization by the PSL. At low elongation, large triangularity produces even significant additional destabilization, with the mode predominantly m = 2, confined to the outer plasma layers, like predicted in references [see Rosen et al., Phys. Fluids, 18, 482 (1975) and Becker and Lackner, Proc. 6th Int. Conf. Plasma Physics and Controlled Nuclear Fusion Research, Vol. II, p. 401 (1977)]. These results explain the tendencies observed in AUG and will be taken into account in future analyses.