|approved||sherwoood_talk_final.pdf||2018-05-01 15:59:35||Richard Hawryluk|
Author: Richard J. Hawryluk
Requested Type: Pre-Selected Invited
Submitted: 2018-02-20 20:45:43
Princeton Plasma Physics Laboratory
100 Stellarator Road
Princeton, NJ 08540
ITER operation will extend and challenge our understanding and provide pivotal new results at larger plasma scale and burning plasma dynamics. In the area of turbulence and transport studies, ITER will extend our understanding of low ρ* and ν* plasmas and the role of pedestal. Isotope effect studies will provide new insights into gyro-Bohm scaling. Theoretical progress has not only enabled understanding the stability of the pedestal but also its extension to the Super H-mode operating regime. In the area of MHD stability, two issues of paramount importance are disruptions and runaway electron formation. Substantial progress has been made but questions remain. These are especially important at the ITER scale, where ITER is predicted to generate large runaway currents. Plasma-boundary interactions impact the lifetime of components and impurity influx. Recent theoretical predictions are in accord with experimental heat flux measurements to the divertor but predict that ITER will be in a more turbulent operating regime. Two approaches are being pursued to mitigate large type 1 ELMs on ITER: pellet injection and magnetic field perturbations. Recent progress has provided new insights on the fundamental understanding on mitigating and suppressing type 1 ELMs. The injection of high energy neutral beams and the production of alpha particles may destabilize energetic particle instabilities on ITER. This is an area undergoing rapid transition from the quantitative prediction of the onset of a few primarily Alfvenic instabilities to the non-linear prediction of the redistribution and loss of those particles. Improved understanding of transport, MHD stability, plasma boundary effects, and energetic particles provides the basis for integrated modeling, predicting the performance of ITER in preparation for experiments. The challenge is to develop sufficient validation and confidence in our predictions to develop entirely new operating regimes with improved performance.