Simulations of the L-H transition on experimental advanced superconducting Tokamak
Artikel i vetenskaplig tidskrift, 2014

We have simulated the L-H transition on the EAST tokamak [Baonian Wan, EAST and HT-7 Teams, and International Collaborators, "Recent experiments in the EAST and HT-7 superconducting tokamaks," Nucl. Fusion 49, 104011 (2009)] using a predictive transport code where ion and electron temperatures, electron density, and poloidal and toroidal momenta are simulated self consistently. This is, as far as we know, the first theory based simulation of an L-H transition including the whole radius and not making any assumptions about where the barrier should be formed. Another remarkable feature is that we get H-mode gradients in agreement with the alpha - alpha(d) diagram of Rogers et al. [Phys. Rev. Lett. 81, 4396 (1998)]. Then, the feedback loop emerging from the simulations means that the L-H power threshold increases with the temperature at the separatrix. This is a main feature of the C-mod experiments [Hubbard et al., Phys. Plasmas 14, 056109 (2007)]. This is also why the power threshold depends on the direction of the grad B drift in the scrape off layer and also why the power threshold increases with the magnetic field. A further significant general H-mode feature is that the density is much flatter in H-mode than in L-mode.

Alcator C-Mod

Toroidal Rotation

Internal Transport Barriers

Resistive Ballooning Modes

Edge Plasmas

Författare

Jan Weiland

Chalmers, Teknisk fysik, Nukleär teknik

Physics of Plasmas

1070-664X (ISSN) 1089-7674 (eISSN)

Vol. 21 12 article no:122501- 122501

Drivkrafter

Hållbar utveckling

Ämneskategorier

Subatomär fysik

Annan teknik

Styrkeområden

Energi

Fundament

Grundläggande vetenskaper

DOI

10.1063/1.4901597