Publication

Identification of the primary processes that lead to the drop in divertor target ion current at detachment in TCV

Publications associées (28)

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

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

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

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

Re-design of EU DEMO with a low aspect ratio

Hartmut Zohm

The design point that had been chosen for EU DEMO in 2016 is reviewed here and a modification is proposed with a lower aspect ratio. Previously the same aspect ratio, A, was chosen for EU DEMO as in major tokamak experiments including ITER (A = 3.1), and, ...

2024

Numerical study of divertor detachment in TCV H-mode scenarios

Holger Reimerdes, Christian Gabriel Theiler, Filippo Bagnato, Davide Galassi, Sophie Danielle Angelica Gorno

The effect of divertor closure and nitrogen seeding on the detachment process has been studied by performing 2D numerical simulations of tokamak a configuration variable (TCV) H-mode divertor scenarios with the SOLEDGE3X-EIRENE edge plasma transport code. ...

Iop Publishing Ltd2023

The role of plasma-atom and molecule interactions on power & particle balance during detachment on the MAST Upgrade Super-X divertor

Christian Gabriel Theiler, Kevin Henricus Annemarie Verhaegh

This paper shows first quantitative analysis of the detachment processes in the MAST Upgrade Super-X divertor (SXD). We identify an unprecedented impact of plasma-molecular interactions involving molecular ions (likely D2+ ), resulting in strong ion sinks ...

IOP Publishing Ltd2023

Tritium removal from JET-ILW after T and D-T experimental campaigns

Henri Weisen, Mikhail Maslov

After the second Deuterium-Tritium Campaign (DTE2) in the JET tokamak with the ITER-Like Wall (ILW) and full tritium campaigns that preceded and followed after the DTE2, a sequence of fuel recovery methods was applied to promote tritium removal from wall c ...

IOP Publishing Ltd2023

Spectroscopic characterisation of TCV divertor towards a detached regime

Lorenzo Martinelli

The challenge of power exhaust of the high heat and particle fluxes foreseen for ITER and the forthcoming nuclear fusion reactors can be mitigated by operating in a detached divertor regime. This regime has been the object of three decades of studies, as i ...

EPFL2023

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

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

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

Fast ion generation with ICRF waves and beams in the Wendelstein 7-X stellarator

Mike Machielsen

The largest operating stellarator, Wendelstein 7-X, is of the quasi-isodynamic type. For this design to scale up to a fusion reactor, several criteria must be met, one of them being good fast ion confinement. The latter still has to be tested experimentall ...

EPFL2023

Global fluid simulation of plasma turbulence in a stellarator with an island divertor

Joaquim Loizu Cisquella, Paolo Ricci, Maurizio Giacomin, António João Caeiro Heitor Coelho

Results of a three-dimensional, flux-driven, electrostatic, global, two-fluid turbulence simulation for a five-field period stellarator with an island divertor are presented. The numerical simulation is carried out with the GBS code, recently extended to s ...

IOP Publishing Ltd2022

New insights on divertor parallel flows,E x B drifts, and fluctuations from in situ, two-dimensional probe measurement in the Tokamak a Configuration Variable

Basil Duval, Holger Reimerdes, Christian Gabriel Theiler, Hugo De Oliveira, Cedric Kar-Wai Tsui, Sophie Danielle Angelica Gorno, Artur Perek

In situ, two-dimensional (2D) Langmuir probe measurements across a large part of the TCV outer divertor are reported in L-mode discharges with and without divertor baffles. This provides detailed insights into time averaged profiles, particle fluxes, and f ...

IOP Publishing Ltd2022

Simultaneous measurements of unstable and stable Alfven eigenmodes in JET

Ambrogio Fasoli, Mario Ludovico Podesta, Paulo Giovane Paschoali Pereira Puglia

In this paper, we report the novel experimental observation of both unstable and stable toroidicity-induced Alfven eigenmodes (TAEs) measured simultaneously in a JET tokamak plasma. The three-ion-heating scheme (D-DNBI-He-3) is employed to accelerate deute ...

IOP Publishing Ltd2022

Gentle nano-electrospray ion source for reliable and efficient generation of microsolvated ions

Oleg Boyarkine, Vladimir Kopysov, Andrei Zviagin

We present herein the design of a nano-electrospray ion source capable of reliable generation of large quantities of microsolvated ions. The source is based on a triple molecular skimmer scheme and can be quickly tuned to generate bare ions or their ionic ...

AIP Publishing2022

A study of the influence of plasma-molecule interactions on particle balance during detachment

Basil Duval, Christian Gabriel Theiler, Kevin Henricus Annemarie Verhaegh, Mirko Wensing, Artur Perek

In this work we provide experimental insights into the impact of plasma-molecule interactions on the target ion flux decrease during divertor detachment achieved through a core density ramp in the TCV tokamak. Our improved analysis of the hydrogen Balmer s ...

Elsevier2021

Physics and applications of three-ion ICRF scenarios for fusion research

Henri Weisen, Mikhail Maslov, Javier García Hernández, Samuele Mazzi

This paper summarizes the physical principles behind the novel three-ion scenarios using radio frequency waves in the ion cyclotron range of frequencies (ICRF). We discuss how to transform mode conversion electron heating into a new flexible ICRF technique ...

2021

Ion cyclotron resonance heating with shifted separatrix

Jonathan Graves, Hamish William Patten

Ion cyclotron resonance heating, which we refer to as ICRH-SS, with the quasilinear (QL) separatrix (i.e., the separatrix in the space of QL routes of ion acceleration) located in the region of passing particles is studied. The aim of ICRH-SS is to minimiz ...

IOP Publishing Ltd2021

Negative hydrogen ion dynamics inside the plasma volume of a linear device: Estimates from particle-in-cell calculations

Philippe Frédérique Bruno Guittienne, Alan Howling, Ivo Furno, Rémy Jacquier, Riccardo Agnello

Negative hydrogen or deuterium ions are the precursor particles used to generate a high power beam of neutrals in order to heat the tokamak plasma core of magnetic fusion devices, inject current, and to some extent control instabilities. In the case of ITE ...

2021

Impact of the new TCV baffled divertor upgrade on pedestal structure and performance

Patrick Blanchard, Basil Duval, Holger Reimerdes, Benoît Labit, Christian Gabriel Theiler, Antoine Pierre Emmanuel Alexis Merle, Umar Sheikh, Davide Galassi

A new set of carbon tiles, neutral beam heating optics and gas baffles were installed on TCV during thebaffled divertor upgrade in early 2019. The installation of the baffles allows a deconvolution of the roles ofmain chamber and divertor neutral pressure ...

Elsevier2021