Gyrokinetic simulations of particle transport in pellet fuelled JET discharges
Journal article, 2017

Pellet injection is a likely fuelling method of reactor grade plasmas. When the pellet ablates, it will transiently perturb the density and temperature profiles of the plasma. This will in turn change dimensionless parameters such as a/Ln,a/LT and plasma β. The microstability properties of the plasma then changes which influences the transport of heat and particles. In this paper, gyrokinetic simulations of a JET L-mode pellet fuelled discharge are performed. The ion temperature gradient/trapped electron mode turbulence is compared at the time point when the effect from the pellet is the most pronounced with a hollow density profile and when the profiles have relaxed again. Linear and nonlinear simulations are performed using the gyrokinetic code GENE including electromagnetic effects and collisions in a realistic geometry in local mode. Furthermore, global nonlinear simulations are performed in order to assess any nonlocal effects. It is found that the positive density gradient has a stabilizing effect that is partly counteracted by the increased temperature gradient in the this region. The effective diffusion coefficients are reduced in the positive density region region compared to the intra pellet time point. No major effect on the turbulent transport due to nonlocal effects are observed.

Author

Daniel Tegnered

Chalmers, Earth and Space Sciences, Plasma Physics and Fusion Energy

Michael Oberparleiter

Chalmers, Earth and Space Sciences, Plasma Physics and Fusion Energy

Hans Nordman

Chalmers, Earth and Space Sciences, Plasma Physics and Fusion Energy

Pär Strand

Chalmers, Earth and Space Sciences, Plasma Physics and Fusion Energy

Luca Garzotti

Culham Lab

I. Lupelli

Culham Lab

C. M. Roach

Culham Lab

M. Romanelli

Culham Lab

Martin Valovic

Culham Lab

Plasma Physics and Controlled Fusion

0741-3335 (ISSN) 1361-6587 (eISSN)

Vol. 59 10 Art.no. 105005-

Driving Forces

Sustainable development

Areas of Advance

Energy

Roots

Basic sciences

Subject Categories

Fusion, Plasma and Space Physics

DOI

10.1088/1361-6587/aa7a84

More information

Created

10/7/2017