Publication
Diverted negative triangularity plasmas on DIII-D: the benefit of high confinement without the liability of an edge pedestal
Related publications (34)
Divertor turbulence characterisation using Gas Puff Imaging in the TCV tokamak
The performance of magnetic confinement fusion devices, such as tokamaks, is strongly correlated to the phenomena that occur in the boundary region of the plasma core that faces the wall of the device. The dominant cross-field transport mechanisms from the ...
EPFL2024An experimental and computational study of tokamak plasma turbulence
Turbulence driven by small-scale instabilities results in strong heat and particle transport, which significantly shortens the confinement time and prevents the formation of a self-sustained plasma reaction in magnetic confinement devices. Control and poss ...
EPFL20233D Characterisation of Turbulent Plasma Filaments Using Gas Puff Imaging in the Tokamak à Configuration Variable
A key challenge for the development of fusion reactors based on magnetic confinement, such as tokamaks and stellarators, is the control of the turbulent processes. The most prominent feature of turbulence in the Scrape-Off Layer (SOL), the volume between t ...
EPFL2023Full-discharge simulation and optimization with the RAPTOR code, from present tokamaks to ITER and DEMO
Tokamak devices aim to magnetically confine a hydrogen plasma at sufficiently high pressure to achieve net energy production from nuclear fusion of light isotopes. Predictive modeling and optimization is crucial for reliable operation of tokamak reactors, ...
EPFL2023Electron temperature fluctuation measurements with Correlation Electron Cyclotron Emission in L-mode and I-mode plasmas at ASDEX Upgrade
The Correlation Electron Cyclotron Emission (CECE) diagnostic at ASDEX Upgrade (AUG) is used to investigate the features of outer core and pedestal (rho(pol) = 0.85-1.0) turbulence across confinement regime transitions. The I-mode confinement regime is a p ...
E D P SCIENCES2023Magnetic control of tokamak plasmas through deep reinforcement learning
Olivier Sauter, Ambrogio Fasoli, Basil Duval, Stefano Coda, Jean-Marc Moret, Federico Alberto Alfredo Felici, Cristian Sommariva, Antoine Pierre Emmanuel Alexis Merle, Cristian Galperti, Francesco Carpanese, Jonas Buchli, Federico Pesamosca, Brendan Tracey, Jonas Degrave
Nuclear fusion using magnetic confinement, in particular in the tokamak configuration, is a promising path towards sustainable energy. A core challenge is to shape and maintain a high-temperature plasma within the tokamak vessel. This requires high-dimensi ...
2022Nonlocal effects in negative triangularity TCV plasmas
Olivier Sauter, Stefano Coda, Laurent Villard, Stephan Brunner, Zhouji Huang, Gabriele Merlo, Claudio Marini
Global gradient driven gyrokinetic simulations performed with the Gyrokinetic Electromagnetic Numerical Experiment (GENE) code are used to investigate Tokamak a configuration variable (TCV) plasmas with negative triangularity. Considering limited L-mode pl ...
IOP PUBLISHING LTD2021Rapid optimization of stationary tokamak plasmas in RAPTOR: demonstration for the ITER hybrid scenario with neural network surrogate transport model QLKNN
Olivier Sauter, Federico Alberto Alfredo Felici, Michele Marin, Simon Van Mulders
This work presents a fast and robust method for optimizing the stationary radial distribution of temperature, density and parallel current density in a tokamak plasma and its application to first-principle-based modeling of the ITER hybrid scenario. A new ...
2021H-mode grade confinement in L-mode edge plasmas at negative triangularity on DIII-D
Olivier Sauter, Alessandro Marinoni
Plasmas with a negative triangularity shape have been created on the DIII-D tokamak that, despite maintaining standard L-mode edge radial profiles, reach volume averaged pressure levels typical of H-mode scenarios. Within the auxiliary power available for ...
2019Effects of collisionality and T e /T i on fluctuations in positive and negative δ tokamak plasmas
Olivier Sauter, Ambrogio Fasoli, Stefano Coda, Stephan Brunner, Laurie Porte, Gabriele Merlo, Matteo Fontana, Ajay Chandrarajan Jayalekshmi
The effects of negative triangularity () on confinement and fluctuations in plasmas covering a large range of parameters were investigated on the tokamak à configuration variable (TCV). The conditions explored in this paper include discharges where neutral ...
2019