Abstract
The application of resonant magnetic perturbations (RMPs) induces striated heat fluxes on the divertor plate in tokamaks. These striated heat fluxes were previously considered strike point splitting by the intersection between the divertor and predicted magnetic lobe structures. Recently, the existence of stationary 3D filaments has been observed for the first time in National Spherical Torus Experiment (NSTX) plasmas with toroidal mode number n = 3 RMPs. Magnetic field line tracing of these filaments from the midplane to the divertor is consistent with the quantity and the radial and toroidal location of striated heat fluxes observed on the divertor. This study suggests that divertor striated heat flux patterns are linked to these stationary filaments rather than to strike point splitting or magnetic lobe structures for NSTX. This finding will help guide future efforts to understand the heat flux striations in NSTX with RMPs in order to control and reduce the divertor peak heat flux.
| Original language | English |
|---|---|
| Article number | 096004 |
| Journal | Nuclear Fusion |
| Volume | 65 |
| Issue number | 9 |
| DOIs | |
| State | Published - Sep 1 2025 |
Funding
The authors gratefully acknowledge Dr Stewart Zweben for his continued support, and Dr Yang Ren, Dr Qiming Hu, Dr SeongMoo Yang and Dr SangKyeun Kim for the useful discussion. This work is supported by DOE contract No. DE-SC0008309 at the University of Tennessee, DE-AC02-09CH11466 at Princeton Plasma Physics Laboratory, and DE-AC52-07NA27344 at Lawrence Livermore National Laboratory.
Keywords
- RMPs
- divertor heat flux
- filaments
- tokamaks