OEDGE Modeling of C Deposition in the Inner Divertor of DIII-D.

Elder, J. D. ; Stangeby, P. C. ; Whyte, D. G. ; Allen, S. L. ; McLean, A. ; Boedo, J. A. ; Bray, B. D. ; Brooks, N. H. ; Fenstermacher, M. E. ; Groth, M. ; Lasnier, C. J.

Technical Information Center Oak Ridge Tennessee

关键词: Plasma;    Doublet-3 device;    Divertors;    Carbon;    Deposition;   

RP-ID  :  DE200515011802

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

Use of carbon in tokamaks leads to a major tritium retention issue due to co-deposition. To investigate this process a low power (no beams) L-mode experiment was performed on DIII-D in which (sup 13)CH(sub 4) was puffed into the main vessel through the toroidally-symmetric pumping plenum at the top of lower single-null discharges. Subsequently, the (sup 13)C content of tiles taken from the vessel wall was measured. The interpretive OEDGE code was used to model the results. It was found that the (sup 13)C deposition pattern is controlled by: (a) source strength of (sup 13)C(sup +), (b) radial location of the (sup 13)C(sup +) source, (c) D(sub (perpendicular)), (d) M(sub (parallel)), the scrape-off layer parallel Mach number. Best agreement was found for (a) (approx.) 50% conversion efficiency ((sup 13)CH(sub 4) (yields) (sup 13)C(sup +), (b) (sup 13)C(sup +) source (approx.) 3.5 cm outboard of separatrix near (sup 13)CH(sub 4) injection location, (c) D(sub (perpendicular)) (approx.) 0.3 m(sup 2)s(sup -1), (d) M(sub (parallel)) (approx.) 0.4 toward inside.