X. Litaudon
A5025673577- Magnetic confinement fusion research
- Fusion materials and technologies
- Superconducting Materials and Applications
- Particle accelerators and beam dynamics
- Ionosphere and magnetosphere dynamics
- Plasma Diagnostics and Applications
- Laser-Plasma Interactions and Diagnostics
- Nuclear reactor physics and engineering
- Gyrotron and Vacuum Electronics Research
- Solar and Space Plasma Dynamics
- Quantum chaos and dynamical systems
- Physics of Superconductivity and Magnetism
- Nuclear Physics and Applications
- High-Energy Particle Collisions Research
- Antenna Design and Analysis
- Dust and Plasma Wave Phenomena
- Integrated Circuits and Semiconductor Failure Analysis
- Electromagnetic Launch and Propulsion Technology
- Atomic and Molecular Physics
- Acoustic Wave Resonator Technologies
- Ion-surface interactions and analysis
- Fluid Dynamics and Turbulent Flows
- Nuclear Engineering Thermal-Hydraulics
- Laser-induced spectroscopy and plasma
- Radiation Effects in Electronics
CEA Cadarache
2013-2025
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2013-2025
Institut de Recherche sur la Fusion par Confinement Magnétique
1998-2024
Culham Science Centre
2009-2024
Royal Military Academy
2020
Japan Atomic Energy Agency
2004-2012
Korea Institute of Fusion Energy
2011
Institute of Plasma Physics
2011
Instituto de Engenharia de Sistemas e Computadores Investigação e Desenvolvimento
2011
Seoul National University
2011
Significant progress has been made in the area of advanced modes operation that are candidates for achieving steady state conditions a fusion reactor. The corresponding parameters, domain operation, scenarios and integration issues discussed this chapter. A review presently developed scenarios, including discussions on operational space, is given. heating current drive recent years, especially off-axis drive, which essential achievement required profile. actuators necessary to produce...
This paper is an overview of recent results relating to turbulent particle and heat transport, the triggering internal transport barriers (ITBs). The dependence pinch velocity on plasma parameters has been clarified compared with experiment. Magnetic shear collisionality are found play a central role. Analysis made progress along two directions: dimensionless scaling laws, which agree prediction for electrostatic turbulence, analysis modulation experiments, provide stringent test models....
The 2014–2016 JET results are reviewed in the light of their significance for optimising ITER research plan active and non-active operation. More than 60 h plasma operation with first wall materials successfully took place since its installation 2011. New multi-machine scaling type I-ELM divertor energy flux density to is supported by principle modelling. relevant disruption experiments modelling reported a set three mitigation valves mimicking setup. Insights L–H power threshold Deuterium...
METIS is a numerical code aiming at fast full tokamak plasma analyses and predictions. It combines 0D scaling-law normalised heat particle transport with 1D current diffusion modelling 2D equilibria. contains several heat, impurities models, as well particle, momentum sources, which allow faster than real time scenario simulations. This paper gives first comprehensive description of the suite: overall structure code, main available details on simulation workflow implementation. Some examples...
Abstract 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 ITER-like Be/W wall. development started pure Deuterium refinement of current, and toroidal magnetic field choices succeeded solving heat load challenges arising 37 MW injected power ITER like environment, keeping radiation edge core controlled, avoiding MHD instabilities reaching high neutron rates. have re-run Tritium...
Stable and stationary states with hollow current density profiles have been achieved in Tore Supra lower hybrid drive (LHCD) during reduced toroidal magnetic field operation weak LH absorption regimes. For these plasma conditions, off-axis power deposition are obtained a reproducible manner when the internal caustics prevent central of waves. In multipass wave propagation regime, validity statistical treatment stochastic diffusion is shown both theoretically experimentally. When large...
A 20 MW/5 GHz lower hybrid current drive (LHCD) system was initially due to be commissioned and used for the second mission of ITER, i.e. Q = 5 steady state target. Though not part currently planned procurement phase, it is now under consideration an earlier delivery. In this paper, both physics technology conceptual designs are reviewed. Furthermore, appropriate work plan also developed. This design, R&D, installation a MW LHCD on ITER follows Scientific Technical Advisory Committee...
Abstract ITER is of key importance in the European fusion roadmap as it aims to prove scientific and technological feasibility a future energy source. The EUROfusion consortium labs within Europe contributing preparation exploitation operation aspires exploit outcomes view DEMO. paper provides an overview major progress obtained recently, carried out frame new (initiated 2021) work-package called ‘ Pr eparation I TER O peration’ (PrIO). directly supported by eleven PrIO contributions given...
The observation of internal transport barriers (ITBs) in which ion thermal diffusivity is reduced to a neoclassical level has been made for the first time tokamak plasmas fueled with deuterium and tritium ions using broad current density profile. heating profiles required obtain an ITB are similar D-T D-D plasmas. Central temperatures 40 keV plasma pressure gradients ${10}^{6}\mathrm{Pa}/\mathrm{m}$ were observed plasma, leading fusion triple product...
Analysis of experiments performed at different heating powers and magnetic field intensities shows that the existence internal transport barriers in JET can be inferred regions space-time where ratio ion gyroradius to local gradient scale length exceeds some critical value. A possible interpretation leading theoretical relevance this dimensionless parameter as a indicator bifurcated plasma state is stabilization turbulence by E×B shear flows associated with large pressure gradients rotation....
The global energy confinement of combined ohmic and lower hybrid driven TORE SUPRA plasmas has been analysed at various densities. In contradiction to the L mode ITER scaling law, this analysis indicates that time depends strongly on plasma density. Furthermore, thermal electron content steady state discharges is found be in good agreement with Rebut-Lallia-Watkins (RLW) law. Current ramp experiments show an enhancement internal inductance, li. These results have extended regimes current...
In 2003, the performance of 'hybrid' regime was successfully validated in JET experiments up to βN = 2.8 at low toroidal field (1.7 T), with plasma triangularity and normalized Larmor radius (ρ*) corresponding identical ASDEX Upgrade discharges. Stationary conditions have been achieved fusion figure merit ( ) reaching 0.42 q95 3.9. The discharges show similar MHD, edge current profile behaviour, when compared Upgrade. addition, extended hybrid scenario operation higher 2.4 T lower ρ* towards...
Real-time simultaneous control of several radially distributed magnetic and kinetic plasma parameters is being investigated on JET, in view developing integrated advanced tokamak scenarios. This paper describes the new model-based profile controller which has been implemented during 2006–2007 experimental campaigns. The aims to use combination heating current drive (H&CD) systems—and optionally poloidal field (PF) system—in an optimal way regulate evolution parameter profiles such as...
Self-consistent transport simulation of ITER scenarios is a very important tool for the exploration operational space and scenario optimisation. It also provides an assessment compatibility developed (which include fast transient events) with machine constraints, in particular poloidal field (PF) coil system, heating current drive (H&CD), fuelling particle energy exhaust systems. This paper discusses results predictive modelling all reference variants using two suite linked equilibrium...
Abstract JET returned to deuterium-tritium operations in 2023 (DTE3 campaign), approximately two years after DTE2. DTE3 was designed as an extension of JET's 2022-2023 deuterium campaigns, which focused on developing scenarios for ITER and DEMO, integrating in-depth physics understanding control schemes. These were evaluated with mixed D-T fuel, using the only remaining tritium-capable tokamak until its closure 2023. A core-edge-SOL integrated H-mode scenario developed tested D-T, showing...
Recent progress in experimental and theoretical studies of edge localized mode (ELM) physics is reviewed for the reactor relevant plasma regimes, namely high confinement that is, H-modes advanced scenarios.
Quasi-steady operation has been achieved at JET in the high-confinement regime with internal transport barriers (ITBs). The ITB maintained up to 11 s. This duration, much larger than energy confinement time, is already approaching a current resistive time. high-performance phase limited only by plant constraints. radial profiles of thermal electron and ion pressures have steep gradients typically mid-plasma radius. A large fraction non-inductive (above 80%) sustained throughout poloidal beta...
Quasistationary operation has been achieved on the Joint European Torus tokamak in internal-transport-barrier (ITB) scenarios, with discharge time limited only by plant constraints. Full current drive was obtained over all high performance phase using lower hybrid drive. For first feedback control total pressure and electron temperature profile implemented using, respectively, neutral beams ion-cyclotron waves. Although impurity accumulation could be a problem steady state ITBs, these...
In order to simultaneously control the current and pressure profiles in high performance tokamak plasmas with internal transport barriers (ITB), a multi-variable model-based technique has been proposed. New algorithms using truncated singular value decomposition (TSVD) of linearized model operator retaining distributed nature system have implemented JET system. Their simplest versions applied density profile reversed shear three heating drive actuators (neutral beam injection, ion cyclotron...
The fusion performance of JET plasmas can be enhanced by the generation internal transport barriers. influence theq-profile shape in local and global plasma has been investigated cases where core magnetic shear ranges from small positive to large negative. Internal barriers extending radii effective raising plasma. It is found that such tend generated more easily if q-profile contains a region negative shear. formation favoured neutral beam injection compared with ion cyclotron resonance...
Plasmas regimes with improved core energy confinement properties, i.e. internal transport barriers (ITB), provide a possible route towards simultaneous high fusion performance and continuous tokamak reactor operation in non-inductive current drive state. High should be made compatible dominant fraction of the plasma self-generated (pressure-driven) by bootstrap effect while operating at normalized pressure moderate current. Furthermore, ITB 'non-stiff' break link observed standard inductive...
In plasmas exhibiting an internal transport barrier (ITB), locally very high pressure gradient (?P) is obtained. It induces values of the magnetohydrodynamic ? parameter (? = ?q 2 ?R?P/P, with R major radius, q safety factor, P pressure, radial and ratio between kinetic magnetic pressure). Similarly to low or negative shear (s), reduces curvature B drifts driving curvature-type microinstabilities. Therefore, can stabilize part microturbulence, which leads higher even ?. This possibility for...
This paper describes a new technique which has been implemented on the JET tokamak to investigate integrated real-time control of several plasma profiles simultaneously (such as current, temperature and pressure) reports results first experimental tests. The are handled through their projection suitable basis functions according Galerkin scheme. Their response three actuators (heating current drive powers injected in plasma) is linearized an experimentally deduced multi-input multi-output...
A new ITER-relevant lower hybrid current drive (LHCD) launcher, based on the passive-active-multijunction (PAM) concept, was brought into operation Tore Supra tokamak in autumn 2009. The PAM launcher concept designed view of ITER to allow efficient cooling waveguides, as required for long pulse operation. In addition, it offers low power reflection close cut-off density, which is very attractive ITER, where large distance between plasma and wall may bring density front values. first...