Manipulation of E × B drifts in a slot divertor with advanced shaping to optimize detachment

Nuclear Fushion

article

Hailong Du¹  H.Y. Guo²  P.C. Stangeby³  Xavier Bonnin⁴  Guoyao Zheng¹  Xuru Duan¹  Min Xu¹ 

[1] Southwestern Institute of Physics;General Atomics;University of Toronto;ITER Organization

关键词: advanced divertor;    cross-field drifts;    plasma-material interactions;    tokamak;   

DOI  :  10.1088/1741-4326/abb53f

来源: Institute of Physics Publishing Ltd.

【 摘 要 】

SOLPS-ITER edge code analysis including drifts shows that optimization of divertor target shaping in a small angle slot (SAS) can strongly influenceE× Bdrift particle fluxes, potentially improving divertor detachment for both toroidal field directions. This is enabled by directing recycling neutrals toward the separatrix from both the common flux region (CFR) and the private flux region (PFR) walls of the slot with a V-shape target in the slot (SAS-V), leading to two separate reinforcing effects, each individually involving positive feed-back: (a) increase of neutral recycling at the PFR wall of the slot due to—and causing—strong radialE× Bion flux from the CFR to the PFR; (b) decrease ofE× Bloss of ions out of the outer divertor into the inner divertor via the PFR due to reduction of the radial gradient of electron temperature at the outer target caused by the increased particle retention in the outer divertor. This circumvents the general problem for divertor operation with ionB× ∇Btoward the X-point:E× Bloss of particles from the outer divertor CFR plasma tends to keep it hot and attached. This work identifies a strong interaction between divertor geometry and drifts, a potentially important effect for optimizing advanced divertors for power exhaust in fusion reactors.

【 授权许可】

Unknown