Publications associées à Mining Complex Activities in the Wild via a Single Smartphone Accelerometer

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

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

Global fluid simulations of plasma turbulence in stellarators

António João Caeiro Heitor Coelho

In order to cope with the decarbonization challenge faced by many countries, fusion is one of the few alternatives to fossil fuels for the production of electricity. Two devices invented in the middle of the previous century have emerged as the most promis ...

EPFL2024

Tangentially viewing phase contrast imaging for turbulence measurements in toroidal fusion devices

Stefano Coda

Phase contrast imaging (PCI) is an established and powerful technique for measuring density fluctuations in plasmas and has been successfully applied to several fusion devices. Rooted in a concept first developed for microscopy, PCI belongs to the category ...

2024

Long plasma duration operation analyses with an international multi-machine (tokamaks and stellarators) database

Stefano Coda, Jeffrey Huang

Combined high-fusion performance and long-pulse operation is one of the key integration challenges for fusion energy development in magnetic devices. Addressing these challenges requires an integrated vision of physics and engineering aspects with the purp ...

IOP Publishing Ltd2024

Models implemented in the methodological approach to design the initial STEP first wall contour

Kevin Henricus Annemarie Verhaegh, Dario Vaccaro, Filippo Bagnato, Davide Galassi

The official Spherical Tokamak for Energy Production mission aims to demonstrate the ability to generate net electricity from fusion with the STEP Prototype Power plant. One of the key technological and engineering challenges in fusion power plants is mana ...

Elsevier Science Sa2024

Divertor turbulence characterisation using Gas Puff Imaging in the TCV tokamak

Curdin Tobias Wüthrich

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 ...

EPFL2024

Error field detection and correction studies towards ITER operation

Olivier Sauter, Leonardo Pigatto, Bernhard Sieglin

In magnetic fusion devices, error field (EF) sources, spurious magnetic field perturbations, need to be identified and corrected for safe and stable (disruption-free) tokamak operation. Within Work Package Tokamak Exploitation RT04, a series of studies hav ...

IOP Publishing Ltd2024

Overview of fast particle experiments in the first MAST Upgrade experimental campaigns

Matteo Vallar

MAST-U is equipped with on-axis and off-axis neutral beam injectors (NBI), and these external sources of super-Alfv & eacute;nic deuterium fast-ions provide opportunities for studying a wide range of phenomena relevant to the physics of alpha-particles in ...

IOP Publishing Ltd2024

Experimental study and interpretative modelling of the Power Exhaust in Configurations with Multiple X-Points in TCV

Sophie Danielle Angelica Gorno

Nuclear fusion presents a promising clean energy source to mitigate future energy crises, with magnetic confinement fusion well-positioned to provide a baseload scenario to power future reactors. The unmitigated power exhaust of such reactors threatens its ...

EPFL2024

JET D-T scenario with optimized non-thermal fusion

Mikhail Maslov, Javier García Hernández, Haomin Sun, Michele Marin

In JET deuterium-tritium (D-T) plasmas, the fusion power is produced through thermonuclear reactions and reactions between thermal ions and fast particles generated by neutral beam injection (NBI) heating or accelerated by electromagnetic wave heating in t ...

IOP Publishing Ltd2023

Essay: Overcoming the Obstacles to a Magnetic Fusion Power Plant

Ambrogio Fasoli

Fusion occurs when light nuclei combine to form heavier nuclei. The energy released in this process powers the stars and can provide humankind with a safe, sustainable, and clean source of baseload electricity, a valuable tool in the fight against climate ...

AMER PHYSICAL SOC2023

Validation of D-T fusion power prediction capability against 2021 JET D-T experiments

Mikhail Maslov, Javier García Hernández, Michele Marin

JET experiments using the fuel mixture envisaged for fusion power plants, deuterium and tritium (D-T), provide a unique opportunity to validate existing D-T fusion power prediction capabilities in support of future device design and operation preparation. ...

IOP Publishing Ltd2023

Impact of the turbulence wavenumber spectrum and probing beam geometry on Doppler reflectometry perpendicular velocity measurements

Frank Nüesch, Anita Frank

The perpendicular propagation velocity of turbulent density fluctuations is an important parameter in fusion plasmas, since sheared plasma flows are crucial for reducing turbulence, and thus an essential input parameter for turbulent transport simulations. ...

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

The JET hybrid scenario in Deuterium, Tritium and Deuterium-Tritium

Mikhail Maslov, Javier García Hernández, Matteo Fontana, Haomin Sun

The JET hybrid scenario has been developed from low plasma current carbon wall discharges to the record-breaking Deuterium-Tritium plasmas obtained in 2021 with the ITER-like Be/W wall. The development started in pure Deuterium with refinement of the plasm ...

IOP Publishing Ltd2023

Study of fast-ion-driven toroidal Alfvén eigenmodes impacting on the global confinement in TCV L-mode plasmas

Stephan Brunner, Laurent Villard, Stefano Coda, Javier García Hernández, Aylwin Iantchenko, Justin Richard Ball, Matteo Vallar, Umesh Kumar, Oleg Krutkin, Luke Simons, Jesús Poley Sanjuán, Samuele Mazzi, Baruch Rofman

Following recent observations of unstable Toroidal Alfven Eigenmodes (TAEs) in a counter-current Neutral Beam Injection (NBI) scenario developed in TCV, an in-depth analysis of the impact of such modes on the global confinement and performance is carried o ...

2023

An experimental and computational study of tokamak plasma turbulence

Aylwin Iantchenko

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 ...

EPFL2023

Full-discharge simulation and optimization with the RAPTOR code, from present tokamaks to ITER and DEMO

Simon Van Mulders

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, ...

EPFL2023

Investigation of the interplay between Electron-Cyclotron waves, suprathermal electrons and turbulence in tokamak plasmas

Jean Arthur Cazabonne

Electron-Cyclotron waves are routinely used in tokamaks to heat the plasma and to drive current through the electron channel. Their unique ability to drive very localized current renders them the main foreseen tool for neoclassical tearing mode mitigation ...

EPFL2023

The competing effects of wave amplitude and collisions on multi-ion species suppression of stimulated Brillouin scattering in inertial confinement fusion Hohlraums

Stephan Brunner

Reduction in stimulated Brillouin scattering (SBS) from National Ignition Facility Hohlraums has been predicted through the use of multi-ion species materials on Hohlraum walls. This approach to controlling SBS is based upon introducing a lighter ion speci ...

2023