Publications associées à Effect of collisions on non-adiabatic electron dynamics in ITG-driven microturbulence

Publications associées (50)

Impurity-seeded detachment in conventional and optimized TCV divertor geometry

Nuclear fusion provides a potentially unlimited and clean energy source which motivates the development of fusion power plants. The tokamak is one of the most promising concepts for a future reactor, confining the fusion plasmas in a torus using strong mag ...

EPFL2025

X-point radiation: From discovery to potential application in a future reactor

Holger Reimerdes, Christian Gabriel Theiler, Umar Sheikh, Olivier Claude Martin Février

Power exhaust is a crucial issue for future fusion reactors. Divertor detachment and the required power dissipation fractions of about 95% are foreseen to be achieved by impurity seeding. In a tokamak, at high seeding levels the radiation often concentrate ...

Elsevier2025

Nonlinear simulation of plasma turbulence using a gyrokinetic moment-based approach

Antoine Cyril David Hoffmann

Plasma turbulence plays a fundamental role in determining the performances of magnetic confinement fusion devices, such as tokamaks. Advances in computer science, combined with the development of efficient physical models, have significantly improved our u ...

EPFL2024

Neutral pressure measurement in TCV tokamak using ASDEX-type pressure gauges

Holger Reimerdes, Marcelo Baquero Ruiz, Guang-Yu Sun, Elena Tonello, Marc Noël, Mateusz Gospodarczyk, Hammam Elaian

Probing the neutral gas distribution at the edge of magnetic confinement fusion devices is critical for plasma exhaust studies. In the TCV tokamak, a set of ASDEX-type hot ionization pressure gauges (APGs) has been installed for fast, in situ measurements ...

2025

Mean-field transport equations and energy theorem for plasma edge turbulent transport

Reinart Andreas J. Coosemans

This paper establishes a mean-field equation set and an energy theorem to provide a theoretical basis in view of the development of self-consistent, physics-based turbulent transport models for mean-field transport codes. A rigorous averaging procedure ide ...

Cambridge University Press2024

Plasma state monitoring and disruption characterization using multimodal VAEs

Giulio Romanelli, Olivier Sauter, Alessandro Pau, Yoeri Renier Johannes Poels, Cristina Venturini

When a plasma disrupts in a tokamak, significant heat and electromagnetic loads are deposited onto the surrounding device components. These forces scale with plasma current and magnetic field strength, making disruptions one of the key challenges for futur ...

IOP Publishing Ltd2025

Global fluid simulation of plasma turbulence in stellarators with the GBS code

Paolo Ricci, Joaquim Loizu Cisquella, António João Caeiro Heitor Coelho, Zeno Tecchiolli

The implementation of three-dimensional magnetic fields, such as the ones of stellarators, in the GBS code (Ricci et al 2012 Plasma Phys. Control. Fusion54 124047; Giacomin et al 2022 J. Comput. Phys.464 111294) is presented, and simulation results are dis ...

IOP Publishing Ltd2024

Projection-angle effects when "observing" a turbulent magnetized collapsing molecular cloud: II. Magnetic field

Aris Evangelos Tritsis

Context. Interstellar magnetic fields are thought to play a fundamental role in the evolution of star-forming regions. Polarized thermal dust emission serves as a key probe for understanding the structure of the plane-of-the-sky component of the magnetic f ...

2025

Full-F turbulent simulation in a linear plasma device using a gyro-moment approach

Paolo Ricci, Baptiste Jimmy Frei

Simulations of plasma turbulence in a linear plasma device configuration are presented. These simulations are based on a simplified version of the gyrokinetic (GK) model proposed by Frei et al. [J. Plasma Phys. 86, 905860205 (2020)], where the full-F distr ...

Aip Publishing2024

Operation Above the Greenwald Density Limit in High Performance DIII-d Negative Triangularity Discharges

Olivier Sauter

The density limit in strongly-shaped negative triangularity (NT) discharges is studied experimentally in the DIII-D tokamak. Record-high Greenwald fractions fG are obtained, using gas puff injection only, with values up to near 2, where fG is defined as th ...

IOP Publishing Ltd2025

Physical and unphysical regimes of self-consistent many-body perturbation theory

Riccardo Rossi

In the standard framework of self-consistent many-body perturbation theory, the skeleton series for the self-energy is truncated at a finite order N and plugged into the Dyson equation, which is then solved for the propagator G(N). We consider two examples ...

Scipost Foundation2024

Ultra long turbulent eddies, magnetic topology, and the triggering of internal transport barriers in tokamaks

Stephan Brunner, Justin Richard Ball, Arnas Volcokas

Local nonlinear gyrokinetic simulations of tokamak plasmas demonstrate that turbulent eddies can extend along magnetic field lines for hundreds of poloidal turns when the magnetic shear is very small. By accurately modeling different field line topologies ...

IOP Publishing Ltd2023

A Gyrokinetic Moment Model of the Plasma Boundary in Fusion Devices

Baptiste Jimmy Frei

The overall performance of fusion devices, such as tokamaks, is strongly correlated to the phenomena that occur in the boundary region, the outer plasma region that faces the wall of the device. The boundary plays a crucial role in regulating the heat and ...

EPFL2023

Gyrokinetic simulation of short wavelength ion temperature gradient instabilities in the ADITYA-U tokamak

Laurent Villard, Emmanuel Lanti

In this work, linear and nonlinear collisionless electrostatic simulation studies of the standard and short wavelength ion temperature gradient mode (SWITG) for experimental profiles and parameters of ADITYA-U tokamak are performed using the linear global ...

IOP Publishing Ltd2023

Equilibrium pressure limits in stellarators

Antoine Baillod

This thesis delves into the potential of magnetic fusion energy, and in particular focuses on the stellarator concept. Stellarators use external coils to produce 3-dimensional (3D) magnetic fields that confine a thermonuclear plasma in a topologically toro ...

EPFL2023

Impact of Hysteresis Losses in Hybrid (HTS-LTS) Coils for Fusion Applications

Davide Uglietti

Several conductor designs featuring High Temperature Superconducting (HTS) stacked tapes for fusion coils are being proposed. These conductors are planned to operate in time-varying magnetic field and current; thus, the estimation of AC losses is fundament ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2023

Modeling and analysis of miniaturized magnetorheological valve for fluidic actuation

Sofia Lydia Ntella

Fluidic actuation enables movement in a wide range of mechanical systems, from simple laboratory devices to more complex industrial machinery. Fluids are used to generate motion of mechanical pieces. The term "fluids" encompasses two types of technologies: ...

EPFL2023

Polynomial-time universality and limitations of deep learning

Emmanuel Abbé

The goal of this paper is to characterize function distributions that general neural networks trained by descent algorithms (GD/SGD), can or cannot learn in polytime. The results are: (1) The paradigm of general neural networks trained by SGD is poly-time ...

WILEY2023

CONVERGENCE AND NONCONVERGENCE OF SCALED SELF-INTERACTING RANDOM WALKS TO BROWNIAN MOTION PERTURBED AT EXTREMA

Thomas Mountford

We use generalized Ray-Knight theorems, introduced by B. Toth in 1996, together with techniques developed for excited random walks as main tools for establishing positive and negative results concerning convergence of some classes of diffusively scaled sel ...

Inst Mathematical Statistics-Ims2023

Equilibrium β-limits dependence on bootstrap current in classical stellarators

Hugo Paul Arbez, Jonathan Graves, Joaquim Loizu Cisquella, Antoine Baillod

While it is important to design stellarators with high magnetohydrodynamic stability β-limit, it is also crucial to ensure that good magnetic surfaces exist in a large range of β values. As β increases, pressure-driven currents perturb the vacuum magnetic ...

Cambridge University Press2023