Skip to main content
OSTI.GOVU.S. Department of Energy Office of Scientific and Technical Information
U.S. Department of Energy
Office of Scientific and Technical Information
 

Scaling of Divertor Heat Flux Profile Widths in DIII-D

Conference ·
; ; ; ; ; ;
The width of the divertor heat flux profile w{sub q,div} is of great interest in future large tokamaks as well as many present devices. Previous studies examining the parametric dependence of w{sub q,div} have arrived at diverse scalings in JET, ASDEX-Upgrade, JT60-U, DIII-D, and NSTX with results somewhat at variance with each other. We attempt here to perform a new series of experiments in DIII-D under controlled conditions to obtain scaling of the divertor heat flux peak value, profile width, and divertor plate power as a function of plasma input parameters, with the maximum number of divertor and scrape-off-layer (SOL) diagnostics brought to bear. We performed measurements in lower single-null edge localized mode (ELM) H-mode diverted configurations that were not strongly pumped due to the strike-point positions. We varied the plasma current I{sub p} at constant toroidal field (B{sub T}) and line-averaged density {bar n}{sub e} at constant I{sub p} and B{sub T}. The neutral beam injected power P{sub inj} was changed at constant I{sub p} and BT, B{sub T} at constant I{sub p}, and B{sub T}/I{sub p} at constant q{sub 95}. The divertor heat flux was calculated from infrared camera measurements using a new high-resolution fast-framing IR camera. The IR camera recorded divertor plate surface thermal emission at many-kilohertz frame rates through the whole discharge, so that time-averaged data as well as rapid changes due to ELMs were obtained. The heat flux at each position in the radial profile was calculated at each of the times steps using the THEODOR 2D heat flux analysis code. We show scaling of the divertor peak heat flux and profile width as a function of the parameters varied, and compare with published results from other devices.
Research Organization:
Lawrence Livermore National Laboratory (LLNL), Livermore, CA
Sponsoring Organization:
USDOE
DOE Contract Number:
W-7405-ENG-48
OSTI ID:
966573
Report Number(s):
LLNL-PROC-413814
Country of Publication:
United States
Language:
English

References (9)

Chapter 4: Power and particle control journal June 2007
Survey of target plate heat flux in diverted DIII-D tokamak discharges journal August 1998
Power deposition onto plasma facing components in poloidal divertor tokamaks during type-I ELMs and disruptions journal March 2005
The effect of ELMs on edge plasma scaling in DIII-D journal December 1992
Energy flux to the ASDEX-Upgrade diverter plates determined by thermography and calorimetry journal January 1995
Chapter 1: Overview and summary journal December 1999
Disruption heat loads on the JET MkIIGB divertor journal May 2002
Divertor heat flux scaling with heating power and plasma current in H-mode discharges in the national spherical torus experiment journal June 2007
Multi-machine scaling of the divertor peak heat flux and width for L-mode and H-mode discharges journal March 1999

Similar Records

Divertor heat and particle flux due to ELMs in DIII-D and ASDEX-Upgrade
Conference · Tue Oct 01 00:00:00 EDT 1996 · OSTI ID:463671
The surface eroding thermocouple for fast heat flux measurement in DIII-D
Journal Article · Sun Oct 07 20:00:00 EDT 2018 · Review of Scientific Instruments · OSTI ID:1543206

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
CAMERAS
DIVERTORS
DOUBLET-3 DEVICE
EDGE LOCALIZED MODES
ELECTRIC CURRENTS
HEAT FLUX
PHYSICS
PLASMA
PLATES