Since 18 of December 2019 conferences.iaea.org uses Nucleus credentials. Visit our help pages for information on how to Register and Sign-in using Nucleus.

17–22 Oct 2016
Kyoto International Conference Center
Japan timezone

The Role of Drifts and Radiating Species in Detached Divertor Operation at DIII-D

19 Oct 2016, 14:00
4h 45m
Kyoto International Conference Center

Kyoto International Conference Center

Takaragaike, Sakyo-ku, Kyoto 606-0001 Japan
Poster EXD - Magnetic Confinement Experiments: Plasma–material interactions; divertors; limiters; scrape-off layer (SOL) Poster FIP/2, EX/2, TH/2

Speaker

Dr Adam McLean (Lawrence Livermore National Laboratory)

Description

A comprehensive experimental campaign at DIII-D has advanced understanding and modeling of the effects of drifts and radiating species in diverted plasma up to ITER-relevant collisionality. Unique diagnostic capabilities are employed to show directly that plasma drifts lead to in/out asymmetries as well as shifts in radial parameter profiles throughout the divertor legs, and are a critical factor for predicting detachment onset, and particle and heat fluxes for a detached divertor. These results are reproduced by first-of-its-kind boundary modeling of H-mode discharges with a full physics description of drifts using UEDGE in both toroidal field directions, confirming that the interplay of radial and poloidal E×B drifts are primarily responsible for target asymmetries and localization of high density/low temperature plasma in the scrape-off layer. SOLPS modeling of L-mode Helium discharges with negligible carbon emission suggests that molecules and atomic contributions may play a role in explaining a consistent shortfall in divertor radiation observed in boundary modeling of multiple tokamaks. These and future planned studies of detachment provide valuable physics insight informing the implementation of high-Z plasma facing components at key locations poloidally in DIII-D in 2016.
Country or International Organization USA
Paper Number EX/2-1

Primary author

Dr Adam McLean (Lawrence Livermore National Laboratory)

Presentation materials

There are no materials yet.