Controlling impurity transport in 5D gyrokinetic simulations using a transport barrier
Artikel i vetenskaplig tidskrift, 2025

The effects of transport barriers on impurity transport, specifically helium (He) and tungsten (W), are investigated using the global, flux-driven, full-F, 5D gyrokinetic code GYSELA. The transport barrier is induced by triggering E x B shear via an external poloidal momentum source, thereby stabilizing ITG turbulence and reducing outward heat fluxes. These reductions in particle and heat fluxes due to the transport barrier lead to enhanced confinement, thereby steepening the ion temperature profiles and reducing the heat diffusivity of the main ion species (i.e. deuterium). Impurity transport in both turbulent and neoclassical regimes is investigated under various conditions, with and without the transport barrier, along with a reversed density profile for tungsten. The transport barrier is found to reduce outward impurity transport and enhance neoclassical thermal screening due to the steepened temperature profile. However, it also prevents helium from being flushed out, due to an increased inward Banana-Plateau flux, caused by the poloidal asymmetry of the source. Overall, a transport barrier induced by an E x B shear proves to be an effective mechanism not only for reducing heat fluxes but also for controlling impurity transport.

E x B shear

impurity

transport barrier

gyrokinetic

transport

thermal screening

GYSELA

Författare

G. Lo-Cascio

Max-Planck-Gesellschaft

Univ Lorraine

E. Gravier

Univ Lorraine

M. Lesur

Univ Lorraine

Institut Universitaire de France

T. Reveille

Univ Lorraine

Y. Sarazin

Le Commissariat à l’Énergie Atomique et aux Énergies Alternatives (CEA)

X. Garbet

Le Commissariat à l’Énergie Atomique et aux Énergies Alternatives (CEA)

Nanyang Technological University

K. Lim

Nanyang Technological University

T. Rouyer

Univ Lorraine

Alejandro Yannick Guillevic

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik

Nuclear Fusion

0029-5515 (ISSN) 1741-4326 (eISSN)

Vol. 65 5 056021

Implementation of activities described in the Roadmap to Fusion during Horizon Europe through a joint programme of the members of the EUROfusion consortium

Europeiska kommissionen (EU) (101052200), 2021-01-01 -- 2025-12-31.

Ämneskategorier (SSIF 2025)

Fusion, plasma och rymdfysik

DOI

10.1088/1741-4326/adc5ea

Mer information

Senast uppdaterat

2025-04-29