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arXiv · 1407.7767

Effect of turbulence on electron cyclotron current drive and heating in ITER

F. J. Casson·E. Poli·C. Angioni·R. Buchholz·A. G. Peeters
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Abstract

Non-linear local electromagnetic gyrokinetic turbulence simulations of the ITER standard scenario H-mode are presented for the q=3/2 and q=2 surfaces. The turbulent transport is examined in regions of velocity space characteristic of electrons heated by electron cyclotron waves. Electromagnetic fluctuations and sub-dominant micro-tearing modes are found to contribute significantly to the transport of the accelerated electrons, even though they have only a small impact on the transport of the bulk species. The particle diffusivity for resonant passing electrons is found to be less than 0.15 m^2/s, and their heat conductivity is found to be less than 2 m^2/s. Implications for the broadening of the current drive and energy deposition in ITER are discussed.

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F. J. Casson, E. Poli, C. Angioni, R. Buchholz, A. G. Peeters. 2014-07-29. Effect of turbulence on electron cyclotron current drive and heating in ITER. https://doi.org/10.1088/0029-5515/55/1/012002

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