ELM filament heat loads on plasma facing components in JET and ITER
نویسنده
چکیده
Observations of localized heat loads to ELM filament impact on the main chamber in JET are reviewed and drawn together to form a coherent picture of the exhaust phase of the ELM. Presently available JET data is quantitatively explained by a parallel loss model of ELM filament dynamics, in which the evolution of filament density and temperature proceeds via a competition of radial advection and parallel convective and conductive losses. The fraction of ELM energy reaching the wall increases with ELM amplitude, in rough agreement with a modified interchange scaling of filamentary motion. The model validated on JET data predicts that ~25% and ~4% of the ELM energy would reach the main chamber (mostly the upper baffle) in ITER for natural (20 MJ, ∆W/Wped ~ 13.3%) and mitigated (1 MJ, ∆W/Wped ~ 0.66%) ELMs, respectively.
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