Abstract
Radio-frequency (RF)-enhanced surface erosion of beryllium (Be) plasma-facing components is explored, for the first time, using the ERO code. The code is applied to measured, RF-enhanced edge Be line emission at JET Be outboard limiters, in the presence of high-power, ion cyclotron-resonance heating (ICRH) in L-mode discharges. In this first modelling study, the RF sheath effect from an ICRH antenna on a magnetically connected, limiter region is simulated by adding a constant potential to the local sheath, in an attempt to match measured increases in local Be I and Be II emission of factors of 2-3. It was found that such increases are readily simulated with added potentials in the range of 100-200 V, which is compatible with expected values for potentials arising from rectification of sheath voltage oscillations from ICRH antennas in the scrape-off layer plasma. Absolute erosion values are also estimated within the uncertainties in local plasma conditions.
| Original language | English |
|---|---|
| Number of pages | 7 |
| Journal | PHYSICA SCRIPTA: TOPICAL ISSUES |
| Volume | 2016 |
| DOIs | |
| Publication status | Published - 25 Jan 2016 |
| MoE publication type | A1 Journal article-refereed |
| Event | International Conference on Plasma-Facing Materials and Components for Fusion Applications - Aix-en-Provence, France Duration: 18 May 2015 → 22 May 2015 Conference number: 15 |
Keywords
- beryllium erosion
- ERO
- JET tokamak
- physical sputtering
- plasma edge modelling
- plasma surface interactions
- RF sheath potentials