Effect of B-Field Dependent Particle Drifts on ELM Behavior in the DIII-D Boundary Plasma

Conference · Tue May 18 00:00:00 EDT 2004

DOI:https://doi.org/10.1016/j.jnucmat.2004.10.086· OSTI ID:15014159

Fenstermacher, M; Leonard, A; Porter, G; Boedo, J; Brooks, N; Groth, M; Gray, D; Hollmann, E; Lasnier, C; Petrie, T; Wade, M; Watkins, J; Zeng, L

ELM effects in the DIII-D pedestal and boundary plasmas were measured with multiple fast diagnostics in matched, lower single null, ELMing H-mode discharges with the ion Bx{gradient}B drift toward and away from the divertor. Data show a strong dependence of the delay in inner vs. outer divertor ELM D{sub alpha} emission on drift direction, and a weaker drift dependence of the inner vs. outer delay of the total radiated power, in addition to the strong density dependence seen in previous work [1]. Time dependent modeling of the boundary plasma during an ELM was done with the UEDGE code including a six-species fluid carbon model and the effect of B-field induced particle drifts [2]. The ELM perturbation was modeled as an instantaneous, outer midplane peaked, increase of diffusion coefficients from the top of the pedestal to the outer SOL. The simulations show delays in the ELM perturbation at the inner vs. outer divertor targets that are similar to the measured delays.

• Research Organization: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 15014159
• Report Number(s): UCRL-CONF-204224; TRN: US0802069
• Resource Relation: Journal Volume: 337-339; Conference: Presented at: 16th International Conference on Plasma Surface Interactions, Portland, ME, United States, May 24 - May 28, 2004
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION
CARBON
DIFFUSION
DIVERTORS
DOUBLET-3 DEVICE
PLASMA
SIMULATION
TARGETS