Publications associées à Blob motion and control in simple magnetized plasmas

Scenario optimization for the tokamak ramp-down phase in RAPTOR. Part B: safe termination of DEMO plasmas

Olivier Sauter, Emiliano Fable, Federico Alberto Alfredo Felici, Anna Teplukhina, Simon Van Mulders, Cassandre Ekta Contré

An optimized plasma current ramp-down strategy is critical for safe and fast termination of plasma discharges in a tokamak demonstration fusion reactor (DEMO), both in planned and emergency scenarios, avoiding plasma disruptions and excessive heat loads to ...

Iop Publishing Ltd2024

Gyrokinetic simulation of low-n Alfvenic modes in tokamak HL-2A plasmas

Javier García Hernández, Samuele Mazzi

The turbulence characteristics of plasmas with internal transport barriers in the HL-2A tokamak are analyzed by means of linear gyrokinetic simulations. It is found that turbulence is dominated by the ion temperature gradient (ITG) mode together with large ...

2023

Vlasov simulation of the emissive plasma sheath with energy-dependent secondary emission coefficient and improved modeling for dielectric charging effects

Guang-Yu Sun

A one-dimensional Vlasov-Poisson simulation code is employed to investigate the plasma sheath considering electron-induced secondary electron emission (SEE) and backscattering. The SEE coefficient is commonly treated as constant in a range of plasma simula ...

FRONTIERS MEDIA SA2022

Implementation of energy transfer technique in ORB5 to study collisionless wave-particle interactions in phase-space

Laurent Villard, Alberto Bottino, Emmanuel Lanti, Noé Thomas Elie Ohana, Emanuele Poli

A new diagnostic has been developed to investigate the wave-particle interaction in the phase-space in gyrokinetic particle-in-cell codes. Keeping information about energy transfer terms in the velocity space, the technique has been implemented and tested ...

2021

Model for current drive induced crash cycles in W7-X

Joaquim Loizu Cisquella, Ajay Kumar

In the Wendelstein 7-X (W7-X) stellarator, the vacuum rotational transform, ι, has a flat radial profile and does not cross any major rational resonance. Nevertheless, during plasma operation the ι‐profile can be strongly modified by electron cyclotron cur ...

IOP Publishing Ltd2021

The Alfvenic nature of chromospheric swirls

Andrea Francesco Battaglia, Aleksi Antoine Bossart

Context. Observations show that small-scale vortical plasma motions are ubiquitous in the quiet solar atmosphere. They have received increasing attention in recent years because they are a viable candidate mechanism for the heating of the outer solar atmos ...

EDP SCIENCES S A2021

Edge turbulence in ISTTOK: a multi-code fluid validation

Paolo Ricci, Fabio Riva, Eric Serre, Rogério Manuel Cabete De Jesus Jorge, Davide Galassi

Fluid models used to study the edge plasma region need to be benchmarked against similar conditions given that models can strongly differ in complexity and therefore the results they produce. Via this validation study undertaken through the framework of EU ...

2021

Four-dimensional drift-kinetic model for scrape-off layer plasmas

Paolo Ricci, Rogério Manuel Cabete De Jesus Jorge

A four-dimensional plasma model able to describe the scrape-off layer region of tokamak devices at arbitrary collisionality is derived in the drift-reduced limit. The basis of the model is provided by a drift-kinetic equation that retains the full nonlinea ...

2020

Triple Cherenkov probe measurements on FTU: calibration and runaway energy spectra

Alessandro Grosso, Filippo Bagnato

Characterization and calibration measurements of two Cherenkov probes have been performed in ENEA Frascati's laboratories. Different kinds of radiation have been used, from visible light to x-rays, in order to evaluate possible spurious responses of the pr ...

IOP PUBLISHING LTD2018

Poloidal CX visible light plasma rotation diagnostics in TCV

Claudio Marini

Controlled thermonuclear fusion is the main goal of plasma physics. At the Swiss Plasma Center, the Tokamak `a Configuration Variable (TCV) constitutes the main experiment on fusion research, where high temperature plasmas are confined by means of magneti ...

EPFL2017

Saturated ideak kink/peeling formations described as three-dimensional magnetohydrodynamic tokamak equilibrium states

Wilfred Anthony Cooper, Basil Duval, Olivier Sauter, Trach-Minh Tran, Holger Reimerdes, Laurie Porte, Jonathan Graves, David Pfefferlé, Daniele Brunetti, Andreas Kleiner, Jonathan Marc Philippe Faustin, Madhusudan Raghunathan, Hamish William Patten

Free boundary magnetohydrodynamic equilibrium states with spontaneous three dimensional deformations of the plasma-vacuum interface are computed for the first time. The structures obtained have the appearance of saturated ideal external kink/peeling modes. ...

American Institute of Physics (AIP)2016

A 3D MHD equilibrium description of nonlinearly saturated ideal external kink/peeling structures in tokamaks

Wilfred Anthony Cooper, Basil Duval, Olivier Sauter, Trach-Minh Tran, Holger Reimerdes, Laurie Porte, Jonathan Graves

Novel free boundary magnetohydrodynamic equilibrium states with spontaneous three-dimensional (3-D) deformations of the plasmaâ vacuum interface are computed. The structures obtained look like saturated ideal external kink/peeling modes. Large edge pre ...

Cambridge University Press2015

Plans for the first plasma operation of Wendelstein 7-X

Wendelstein 7-X (W7-X) is currently under commissioning in preparation for its initial plasma operation phase, operation phase 1.1 (OP1.1). This first phase serves primarily to provide an integral commissioning of all major systems needed for plasma operat ...

IOP Publishing Ltd2015

Stability of Tokamak and RFP Plasmas with an Extended Region of Low Magnetic Shear

Daniele Brunetti

It has been observed experimentally that magnetically confined plasmas, characterised by the safety factor q with a small or slightly inverted magnetic shear, have good confinement properties. Such plasmas typically have no internal transport barrier, oper ...

EPFL2015

Improved confinement in high-density H-modes via modification of the plasma boundary with lower hybrid waves

Peng Xu, Christian Gabriel Theiler, Yu Lin

Injecting Lower Hybrid Range of Frequency (LHRF) waves into Alcator C-Mod's high-density H-mode plasmas has led to enhanced global energy confinement by increasing pedestal temperature and pressure gradients, decreasing the separatrix density, modifying th ...

Amer Inst Physics2015

Energetic ion dynamics and confinement in 3D saturated MHD configurations

David Pfefferlé

In the following theoretical and numerically oriented work, a number of findings have been assembled. The newly devised VENUS-LEVIS code, designed to accurately solve the motion of energetic particles in the presence of 3D magnetic fields, relies on a non- ...

EPFL2015

Superdiffusive transport in laboratory and astrophysical plasmas

Ambrogio Fasoli, Ivo Furno, Alexandre Dominique Bovet, Paolo Ricci, Kyle Gustafson

In the last few years it has been demonstrated, both by data analysis and by numerical simulations, that the transport of energetic particles in the presence of magnetic turbulence can be superdiffusive rather than normal diffusive (Gaussian). The term ‘su ...

Cambridge University Press2015

Pre-sheath density drop induced by ion-neutral friction along plasma blobs and implications for blob velocities

Ambrogio Fasoli, Ivo Furno, Joaquim Loizu Cisquella, Christian Gabriel Theiler

The pre-sheath density drop along the magnetic field in field-aligned, radially propagating plasma blobs is investigated in the TORPEX toroidal experiment [Fasoli et al., Plasma Phys. Controlled Fusion 52, 124020 (2010)]. Using Langmuir probes precisely al ...

Amer Inst Physics2014

NBI fast ion confinement in the helical core of MAST hybrid-like plasmas

Wilfred Anthony Cooper, Jonathan Graves, David Pfefferlé, Cyril Misev

Energetic ions are found to be transported strongly from the core of MAST hybrid-like plasmas during long-lived mode (LLM) magnetohydrodynamic activity. The resulting impact on the neutral beam ion deposition and concurrent current drive is modelled usin ...

IOP Publishing Ltd2014

Turbulent regimes in the tokamak scrape-off layer

Sébastien Jolliet, Joaquim Loizu Cisquella, Paolo Ricci, Annamaria Mosetto, Federico David Halpern

We identify the turbulent regimes in the tokamak scrape-off layer as a function of plasma resistivity, electron to ion mass ratio, safety factor, and magnetic shear. We find that two main instabilities drive turbulence in the SOL: Drift Waves, with their r ...

2013