Carbon migration during methane injection experiments under ITER divertor-relevant conditions

[摘要] Methane was injected into a high density low temperature hydrogen plasma beam (n(e) <= 10(21) m (3), T-e similar to 1 eV) in Pilot-PSI to study carbon transport and provide a benchmark case for modeling. Gas injection was performed through molybdenum samples that acted as collectors of redeposits. The CH A-X band emission plumes are localized near the injection hole with a typical width of similar to 3 mm and a decay length of similar to 1.5 mm. The geometry of the emission profile is not influenced by the electron temperature. The redeposition efficiency and codeposit structure depend on the surface temperature. Surface temperatures below 500 K promote growth of a-C:H films across the surface and lead to redeposition of up to 38% of injected carbon. Above 800 K the redeposition efficiency decreases strongly and carbon microparticles are found near the injection hole. (C) 2013 Elsevier B. V. All rights reserved.

[发布日期] 2013-07-01

[效力级别]  Proceedings Paper