Wall conditioning and plasma surface interactions in DIII-D

Conference · Sat Sep 01 04:00:00 EDT 1990

OSTI ID:6446990

Jackson, G L; Petersen, P I; Schaffer, M S; Taylor, P L; Taylor, T S ^[1]; Doyle, B L; Walsh, D S ^[2]; Hill, D N ^[3]; Hsu, W L ^[4]; Winter, J ^[5]

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1. General Atomics, San Diego, CA (USA)
2. Sandia National Labs., Albuquerque, NM (USA)
3. Lawrence Livermore National Lab., CA (USA)
4. Sandia National Labs., Livermore, CA (USA)
5. Kernforschungsanlage Juelich GmbH (Germany, F.R.). Inst. fuer Plasmaphysik

Wall conditioning is used in DIII-D for both reduction of impurity influxes and particle control. The methods used include: baking, pulsed discharge cleaning, hydrogen glow cleaning, helium and neon glow conditioning, and carbonization. Helium glow wall conditioning applied before every tokamak discharge has been effective in impurity removal and particle control and has significantly expanded the parameter space in which DIII-D operates to include limiter and ohmic H-mode discharges and higher {beta}{sub T} at low q. The highest values of divertor plasma current (3.0 MA) and stored energy (3.6 MJ) and peaked density profiles in H-mode discharges have been observed after carbonization. Divertor physics studies in DIII-D include sweeping the X-point to reduce peak heat loads, measurement of particle and heat fluxes in the divertor region, and erosion studies. The DIII-D Advanced Divertor has been installed and bias and baffle experiments will begin in the fall of 1991. 15 refs., 4 figs.

• Research Organization: General Atomics, San Diego, CA (USA)
• Sponsoring Organization: DOE/ER
• DOE Contract Number: AC03-89ER51114
• OSTI ID: 6446990
• Report Number(s): GA-A-20250; CONF-900918--14; ON: DE91001547
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700201* -- Fusion Power Plant Technology-- Blanket Engineering
BAKING
BOUNDARY LAYERS
CLEANING
DIVERTORS
DOUBLET REACTORS
FIRST WALL
HEATING
IMPURITIES
LAYERS
PLASMA IMPURITIES
PLASMA SCRAPE-OFF LAYER
THERMONUCLEAR REACTOR WALLS
THERMONUCLEAR REACTORS
TOKAMAK TYPE REACTORS
WALL EFFECTS