28 / 2021-04-09 17:07:49

Plasma beta effects on the island divertor of Wendelstein 7-X

MHD equilibrium,Divertor,Wendelstein 7-X

To control its heat- and particle-exhaust, Wendelstein 7-X (W7-X) relies on the island

divertor concept. In this divertor topology, a chain of magnetic islands forms a scrape-o

layer between the divertor target plates and the plasma core, yielding high connection

lengths above 100m and wetted areas above 1m2[1]. These favorable properties are in-

strumental to achieve a high-power steady-state plasma in the up-coming experimental

campaigns. In nite-beta magnetohydrodynamic (MHD) equilibrium, the pressure-driven

internal plasma currents can substantially aect the topology of the edge magnetic eld.

This eect is dependent on the magnetic conguration, with the standard (5/5 edge island

chain), high-iota (5/4 edge island chain) and low-iota (5/6 edge island chains) showcasing

dierent responses to increasing plasma pressure.



In this talk, we will present MHD equilibrium simulations for nite-beta plasmas in

dierent magnetic congurations of W7-X. These simulations were calculated with the 3D

MHD equilibrium code HINT. Furthermore, we will present extrapolated changes in the

heat-load structure on plasma-facing components (PFCs) for the up-coming experimental

steady-state campaign, calculated using a simple anisotropic diusion model.