Numerical investigation of plasma edge transport and limiter heat fluxes in Wendelstein 7-X startup plasmas with EMC3-EIRENE
Numerical investigation of plasma edge transport and limiter heat fluxes in Wendelstein 7-X startup plasmas with EMC3-EIRENE
The results of a first systematic assessment of plasma edge transport processes for the limiter startup configuration at Wendelstein 7-X are presented. This includes an investigation of transport from intrinsic and externally injected impurities and their impact on the power balance and limiter heat...
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Personal Name(s): | Effenberg, F. (Corresponding author) |
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Feng, Y. / Schmitz, O. / Frerichs, H. / Bozhenkov, S. A. / Hölbe, H. / König, R. / Krychowiak, M. / Pedersen, T. Sunn / Reiter, D. / Stephey, L. | |
Contributing Institute: |
Plasmaphysik; IEK-4 |
Published in: | Nuclear fusion, 57 (2017) 3, S. 036021 - |
Imprint: |
Vienna
IAEA
2017
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DOI: |
10.1088/1741-4326/aa4f83 |
Document Type: |
Journal Article |
Research Program: |
Plasma-Wall-Interaction |
Link: |
Restricted Restricted OpenAccess OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://dx.doi.org/10.1088/1741-4326/aa4f83 in citations.
The results of a first systematic assessment of plasma edge transport processes for the limiter startup configuration at Wendelstein 7-X are presented. This includes an investigation of transport from intrinsic and externally injected impurities and their impact on the power balance and limiter heat fluxes. The fully 3D coupled plasma fluid and kinetic neutral transport Monte Carlo code EMC3-EIRENE is used.The analysis of the magnetic topology shows that the poloidally and toroidally localized limiters cause a 3D helical scrape-off layer (SOL) consisting of magnetic flux tubes of three different connection lengths L C. The transport in the helical SOL is governed by L C as topological scale length for the parallel plasma loss channel to the limiters. A clear modulation of the plasma pressure with L C is seen. The helical flux tube topology results in counter streaming sonic plasma flows.The heterogeneous SOL plasma structure yields an uneven limiter heat load distribution with localized peaking. Assuming spatially constant anomalous transport coefficients, increasing plasma density yields a reduction of the maximum peak heat loads from 12 MWm−2 to 7.5 MWm−2 and a broadening of the deposited heat fluxes. ... |