Characteristics of microinstabilities in electron cyclotron and ohmic heated discharges
Artikel i vetenskaplig tidskrift, 2011

Characteristics of microinstabilities in electron cyclotron (EC) and ohmic heated (OH) discharges in the T10 tokamak have been analyzed by linear electrostatic gyrokinetic simulations with gyro [J. Candy and R. E. Waltz, J. Comput. Phys. 186, 545 (2003)] aiming to find insights into the effect of auxiliary heating on the transport. Trapped electron modes are found to be unstable in both OH and the EC heated scenarios. In the OH case the main drive is from the density gradient and in the EC case from the electron temperature gradient. The growth rates and particle fluxes exhibit qualitatively different scaling with the electron-to-ion temperature ratios in the two cases. This is mainly due to the fact that the dominant drives and the collisionalities are different. The inward flow velocity of impurities and the impurity diffusion coefficient decreases when applying EC heating, which leads to lower impurity peaking, consistently with experimental observations.

tokamak

fusion plasma physics

turbulent transport

Författare

Istvan Pusztai

Chalmers, Teknisk fysik, Nukleär teknik

Sara Moradi

Chalmers, Teknisk fysik, Nukleär teknik

Tünde Fülöp

Chalmers, Teknisk fysik, Nukleär teknik

Natalia Timchenko

National Research Centre "Kurchatov Institute"

Physics of Plasmas

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

Vol. 18 8 082506- 082506

Drivkrafter

Hållbar utveckling

Styrkeområden

Energi

Fundament

Grundläggande vetenskaper

Ämneskategorier

Fusion, plasma och rymdfysik

DOI

10.1063/1.3620409

Mer information

Skapat

2017-10-07