Fusion is a tremendously promising energy source for mitigating and adapting to climate change. The tokamak is a toroidal plasma confinement system, where a fusion plasma is confined by a magnetic field. The magnetic fields produced by the plasma and external electromagnets also provide the equilibrium conditions necessary for achieving a steady, electricity producing system. There is a grand challenge for optimizing fusion power plants: understanding small-scale turbulent fluctuations and their contributions to transport of heat, particles and momentum in the fusion plasma. This talk will introduce high-performance modes of operation in tokamaks. Especially, the I-mode confinement regime is promising for future reactor operation due to high energy confinement without high impurity particle confinement. However, the role of edge turbulence in creating I-mode’s beneficial transport properties is still not fully understood. New measurements of edge turbulence in I-modes at low and high densities at ASDEX Upgrade will be presented. A high radial resolution correlation electron cyclotron emission radiometer measures broadband turbulence. Linear gyrokinetic simulations of the edge turbulence indicate that while the dominant turbulent modes in the outer core are ion directed and electrostatic, the turbulence becomes increasingly electron directed and electromagnetic with increasing radius. This talk will also discuss next steps for understanding high performance operation modes via detailed turbulence measurements.

Co-sponsored by: MIPSE and SEM NPSS

Speaker(s): Prof. Anne White,

Bldg: 1311 EECS, 1301 Beal Ave, Ann Arbor, Michigan, United States, 48109, Virtual: https://events.vtools.ieee.org/m/301592