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 | United States |
|---|---|
| Paper Number | EX/2-1 |
Primary author
Dr
Adam McLean
(Lawrence Livermore National Laboratory)
Co-authors
A. Briesemeister
(Oak Ridge National Laboratory)
A.L. Moser
(General Atomics)
A.W. Leonard
(General Atomics)
C. Samuell
(Lawrence Livermore National Laboratory)
C. Sang
(Institute of Plasma Physics, Chinese Academy of Sciences)
C.J. Lasnier
(Lawrence Livermore National Laboratory)
D. Rudakov
(University of California San Diego)
D. Thomas
(General Atomics)
D.N. Hill
(General Atomics)
E. Kolemen
(Princeton Plasma Physics Laboratory)
E.A. Unterberg
(Oak Ridge National Laboratory)
G.D. Porter
(Lawrence Livermore National Laboratory)
H. Wang
(Oak Ridge National Laboratory)
H.Y. Guo
(General Atomics)
I. Bykov
(University of California San Diego)
J. Canik
(Oak Ridge National Laboratory)
J. Guterl
(General Atomics)
J.A. Boedo
(University of California San Diego)
J.D. Elder
(University of Toronto Institute for Aerospace Studies)
J.G. Watkins
(Sandia National Laboratory)
M. Fenstermacher
(Lawrence Livermore National Laboratory)
M. Groth
(Aalto University)
M.A. Makowski
(Lawrence Livermore National Laboratory)
P.C. Stangeby
(University of Toronto Institute for Aerospace Studies)
R. Ding
(Institute of Plasma Physics, Chinese Academy of Sciences)
S.L. Allen
(Lawrence Livermore National Laboratory)
T. Abrams
(General Atomics)
T. Rognlien
(Lawrence Livermore National Laboratory)
T.H. Osborne
(General Atomics)
T.W. Petrie
(General Atomics)
W. Meyer
(Lawrence Livermore National Laboratory)
