Abstract
The first operational campaign of Wendelstein 7-X (W7-X) provided an excellent environment for the study of plasma-surface interaction (PSI) in a stellarator. In situ spectroscopic analysis via a combined visible/infrared camera system and a filterscope system revealed that the primary erosion zone was correlated with the high heat flux regions on the limiter. This analysis matched to where the erosion zone was found in the post-mortem analysis, which was done with scanning electron microscopy/focused ion beam/electron dispersive x-ray spectroscopy imaging. Additionally, a region of prompt deposition was found to the inside of these high heat flux zones. A region of far scrape-off layer (SOL) deposition was found at the edges of the limiter tiles. All deposition regions were identified by their homogeneous, increased oxygen content compared to the pure carbon makeup of the limiters. Poloidal variation of the impinging heat flux follow the imprint of the 3D SOL flux tubes. In how far this reflects in the PSI will require further analysis and modeling.
| Original language | English |
|---|---|
| Article number | 014050 |
| Journal | Physica Scripta |
| Volume | 2017 |
| Issue number | T170 |
| DOIs | |
| State | Published - Dec 1 2017 |
| Event | 16th International Conference on Plasma-Facing Materials and Components for Fusion Applications, PFMC 2017 - Neuss/Dusseldorf, Germany Duration: May 16 2017 → May 19 2017 |
Funding
This work has been funded by the US Department of Energy under grants DE-SC0013911, DE-SC0014210, DE-AC05-00OR22725 and DOE LANS Contract No. DE-AC52-06NA25396. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 under Grant Agreement No. 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission.*%blankline%* This work has been funded by the US Department of Energy under grants DE-SC0013911, DE-SC0014210, DE-AC05-00OR22725 and DOE LANS Contract No. DE-AC52–06NA25396. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 under Grant Agreement No. 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission.
| Funders | Funder number |
|---|---|
| US Department of Energy | |
| U.S. Department of Energy | DE-AC05-00OR22725, DE-SC0013911, DE-AC52–06NA25396, DE-SC0014210 |
| Horizon 2020 Framework Programme | 633053 |
| H2020 Euratom |
Keywords
- Deposition
- Erosion
- Plasma-surface interaction
- Scrape-off layer
- W7-X
