Analysis of a multi-machine database on divertor heat fluxes

Journal Article · Tue May 15 00:00:00 EDT 2012 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.4710517· OSTI ID:22072400

Makowski, M A; Lasnier, C J ^[1]; Elder, D; Stangeby, P C ^[2]; Gray, T K; Maingi, R ^[3]; LaBombard, B; Terry, J L ^[4]; Leonard, A W; Osborne, T H ^[5]; Watkins, J ^[6]

---

1. Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)
2. University of Toronto Institute of Aerospace Studies, Toronto M3H 5T6 (Canada)
3. Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)
4. Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)
5. General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)
6. Sandia National Laboratory, Albuquerque, New Mexico 87185 (United States)

A coordinated effort to measure divertor heat flux characteristics in fully attached, similarly shaped H-mode plasmas on C-Mod, DIII-D, and NSTX was carried out in 2010 in order to construct a predictive scaling relation applicable to next step devices including ITER, FNSF, and DEMO. Few published scaling laws are available and those that have been published were obtained under widely varying conditions and divertor geometries, leading to conflicting predictions for this critically important quantity. This study was designed to overcome these deficiencies. Analysis of the combined data set reveals that the primary dependence of the parallel heat flux width is robustly inverse with I{sub p}, which all three tokamaks independently demonstrate. An improved Thomson scattering system on DIII-D has yielded very accurate scrape off layer (SOL) profile measurements from which tests of parallel transport models have been made. It is found that a flux-limited model agrees best with the data at all collisionalities, while a Spitzer resistivity model agrees at higher collisionality where it is more valid. The SOL profile measurements and divertor heat flux scaling are consistent with a heuristic drift based model as well as a critical gradient model.

• OSTI ID: 22072400
• Journal Information: Physics of Plasmas, Vol. 19, Issue 5; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
DIVERTORS
DOUBLET-3 DEVICE
HEAT FLUX
H-MODE PLASMA CONFINEMENT
ITER TOKAMAK
NSTX DEVICE
PLASMA SCRAPE-OFF LAYER
SCALING LAWS
THOMSON SCATTERING
TRANSPORT THEORY