Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10645115 | Journal of Nuclear Materials | 2011 | 6 Pages |
Abstract
Density profiles of He2+, C6+, Ne10+ and Ar16+ are measured at ASDEX Upgrade with high temporal (1.9Â ms) and radial resolution (>3Â mm) using CXRS. This allows the transport coefficients at the edge transport barrier to be analyzed in between type-I ELMs during H-mode. All measurements resemble the neoclassical transport coefficients, which means that the diffusion coefficient ranges from 0.15 to 0.35Â m2/s and the maximum of the inward convection velocity is Z-dependent increasing from 15Â m/s (He2+) to 90Â m/s (Ar16+). These results are combined into a simplified transport-erosion model for W which calculates the neoclassical transport coefficients self-consistently while taking several impurity species into account. The model also calculates erosion fluxes at the wall, prompt re-deposition of W and loss terms due to parallel flows in the scrape-off layer. While several free parameters exist in the model, it demonstrates that a quantitative consistency between the measured erosion fluxes of W and the observed W concentration inside the plasma is obtainable.
Related Topics
Physical Sciences and Engineering
Energy
Nuclear Energy and Engineering
Authors
T. Pütterich, R. Dux, M.A. Janzer, R.M. McDermott, ASDEX Upgrade Team ASDEX Upgrade Team,