First measurements of Hiro currents in vertical displacement event in tokamaks
- Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)
- PPPL, Princeton University, Princeton, New Jersey 08543 (United States)
- Academy of Mathematics and System Sciences, Chinese Academy of Sciences, P.O. Box 2719, Beijing 100190 (China)
Specially designed tiles were setup in the 2012 campaign of the Experimental Advanced Superconducting Tokamak (EAST), to directly measure the toroidal surface currents during the disruptions. Hiro currents with direction opposite to the plasma currents have been observed, confirming the sign prediction by the Wall Touching Vertical Mode (WTVM) theory and numerical simulations. During the initial phase of the disruption, when the plasma begins to touch the wall, the surface currents can be excited by WTVM along the plasma facing tile surface, varying with the mode magnitude. The currents are not observed in the cases when the plasma moves away from the tile surface. This discovery addresses the importance of the plasma motion into the wall in vertical disruptions. WTVM, acting as a current generator, forces the Hiro currents to flow through the gaps between tiles. This effect, being overlooked so far in disruption analysis, may damage the edges of the tiles and is important for the ITER device.
- OSTI ID:
- 22410425
- Journal Information:
- Physics of Plasmas, Vol. 22, Issue 6; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Kink modes and surface currents associated with vertical displacement events
3D simulations of vertical displacement events in tokamaks: A benchmark of M3D-C1, NIMROD, and JOREK