Concept
Matrice triangulaire
Publications associées (122)
Experiments and gyrokinetic simulations of TCV plasmas with negative triangularity in view of DTT operations
Olivier Sauter, Stefano Coda, Justin Richard Ball, Alberto Mariani, Matteo Vallar, Filippo Bagnato
Negative triangularity (NT) scenarios in TCV have been compared to positive triangularity (PT) scenarios using the same plasma shapes foreseen for divertor tokamak test tokamak operations. The experiments provided a NT/PT L-mode pair and a PT H-mode with d ...
Iop Publishing Ltd2024Validation of short-pulse reflectometry turbulence measurements with a synthetic diagnostic
Stefano Coda, Stephan Brunner, Oleg Krutkin, Umesh Kumar, Mackenzie Peter-Fulford Van Rossem, Samuele Mazzi
Experimental measurements of the turbulence amplitude utilizing a short pulse reflectometry method are presented. Two discharges with shaped plasma possessing opposite signs of triangularity are considered and a higher turbulence amplitude is found in the ...
Bristol2024Physical insights from the aspect ratio dependence of turbulence in negative triangularity plasmas
Stefano Coda, Justin Richard Ball
In this work, we study the impact of aspect ratio A = R 0 / r (the ratio of major radius R 0 to minor radius r) on the confinement benefits of negative triangularity (NT) plasma shaping. We use high-fidelity flux tube gyrokinetic GENE simulations and consi ...
Iop Publishing Ltd2024SPEEDING UP KRYLOV SUBSPACE METHODS FOR COMPUTING f(A)b VIA RANDOMIZATION
Daniel Kressner, Alice Cortinovis
This work is concerned with the computation of the action of a matrix function f(A), such as the matrix exponential or the matrix square root, on a vector b. For a general matrix A, this can be done by computing the compression of A onto a suitable Krylov ...
Siam Publications2024First-principle based predictions of the effects of negative triangularity on DTT scenarios
Olivier Sauter, Gabriele Merlo, Alberto Mariani
Plasmas with negative triangularity (NT) shape have been recently shown to be able to achieve H-mode levels of confinement in L-mode, avoiding detrimental edge localised modes. Therefore, this plasma geometry is now studied as a possible viable option for ...
Bristol2024Study of impurity C transport and plasma rotation in negative triangularity on the TCV tokamak
Olivier Sauter, Basil Duval, Stefano Coda, Benoît Labit, Alessandro Pau, Laurie Porte, Alexander Karpushov, Antoine Pierre Emmanuel Alexis Merle, Justin Richard Ball, Dmytry Mykytchuk, Filippo Bagnato
Carbon impurity transport is studied in the TCV tokamak using a charge exchange recombination diagnostic. TCVs flexible shaping capabilities were exploited to extend previous impurity transport studies to negative triangularity (delta < 0). A practical way ...
Iop Publishing Ltd2024NBI optimization on SMART and implications for scenario development
Mario Ludovico Podesta, Francesca Maria Poli
The SMall Aspect Ratio Tokamak (SMART) under commissioning at the University of Seville, Spain, aims to explore confinement properties and possible advantages in confinement for compact/spherical tokamaks operating at negative vs. positive triangularity. T ...
Bristol2024Effect of triangularity on plasma turbulence and the SOL-width scaling in L-mode diverted tokamak configurations
Paolo Ricci, Louis Nicolas Stenger, Davide Mancini, Maurizio Giacomin
The effect of triangularity on tokamak boundary plasma turbulence is investigated using global, flux-driven, three-dimensional, two-fluid simulations. The simulations show that negative triangularity (NT) stabilizes boundary plasma turbulence, and linear i ...
IOP Publishing Ltd2023Estimating the Topology of Preferential Attachment Graphs Under Partial Observability
This work addresses the problem of learning the topology of a network from the signals emitted by the network nodes. These signals are generated over time through a linear diffusion process, where neighboring nodes exchange messages according to the underl ...
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC20233D 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 ...
EPFL2023