Abstract
A radiating divertor approach was successfully applied to high performance 'hybrid' plasmas [M.R. Wade et al., in: Proceedings of the 20th IAEA Fusion Energy Conference, Vilamoura, Portugal, 2004]. Our techniques included: (1) injecting argon near the outer divertor target, (2) enhancing the plasma flow into the inner and outer divertors by a combination of particle pumping and deuterium gas puffing upstream of the divertor targets, and (3) isolating the inner divertor from the outer by a structure in the private flux region. Good hybrid conditions were maintained, as the peak heat flux at the outer divertor target was reduced by a factor of 2.5; the peak heat flux at the inner target decreased by 20%. This difference was caused by a higher concentration of argon at the outer target than at the inner target. Argon accumulation in the main plasma was modest (nAr/ne ≤ 0.004 on axis), although the argon profile was more peaked than the electron profile.
Original language | English |
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Pages (from-to) | 416-420 |
Number of pages | 5 |
Journal | Journal of Nuclear Materials |
Volume | 363-365 |
Issue number | 1-3 |
DOIs | |
State | Published - Jun 15 2007 |
Externally published | Yes |
Funding
This work was supported by the US Department of Energy under DE-FC02-04ER54698, W-7405-ENG-48, DE-AC05-00OR22725, and DE-AC04-94AL85000.
Keywords
- Argon
- DIII-D
- Divertor
- Divertor plasma
- Impurity screening