A5033324428- Magnetic confinement fusion research
- Particle accelerators and beam dynamics
- Ionosphere and magnetosphere dynamics
- Fusion materials and technologies
- Superconducting Materials and Applications
- Laser-Plasma Interactions and Diagnostics
- Plasma Diagnostics and Applications
- Solar and Space Plasma Dynamics
- Gyrotron and Vacuum Electronics Research
- Nuclear Physics and Applications
- Nuclear reactor physics and engineering
- Physics of Superconductivity and Magnetism
- Rare-earth and actinide compounds
- Dust and Plasma Wave Phenomena
- Electric Motor Design and Analysis
- Atomic and Molecular Physics
- Advanced Data Storage Technologies
- Atomic and Subatomic Physics Research
- Magnetic Properties of Alloys
- High-pressure geophysics and materials
- Particle Detector Development and Performance
- Advanced X-ray and CT Imaging
- Laser-induced spectroscopy and plasma
- Electrostatic Discharge in Electronics
- Nuclear physics research studies
CEA Cadarache
2015-2024
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2015-2024
Max Planck Institute for Plasma Physics
2008-2023
Institut de Recherche sur la Fusion par Confinement Magnétique
1996-2022
Southwestern Institute of Physics
2011-2020
Southwest Jiaotong University
2020
École Polytechnique Fédérale de Lausanne
2001-2020
Royal Military Academy
2020
ITER
2011
Culham Science Centre
2011
CRONOS is a suite of numerical codes for the predictive/interpretative simulation full tokamak discharge. It integrates, in modular structure, 1D transport solver with general 2D magnetic equilibria, several heat, particle and impurities models, as well momentum sources. This paper gives first comprehensive description suite: overall structure code, main available details on workflow implementation. Some examples applications to analysis experimental discharges predictions ITER scenarios are...
With WEST (Tungsten Environment in Steady State Tokamak) (Bucalossi et al 2014 Fusion Eng. Des. 89 907–12), the Tore Supra facility and team expertise (Dumont Plasma Phys. Control. 56 075020) is used to pave way towards ITER divertor procurement operation. It consists implementing a configuration installing ITER-like actively cooled tungsten monoblocks tokamak, taking full benefit of its unique long-pulse capability. user platform, open all partners. This paper describes physics basis WEST:...
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...
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 Since the last IAEA Fusion Energy Conference in 2018, significant progress of experimental program HL-2A has been achieved on developing advanced plasma physics, edge localized mode (ELM) control physics and technology. Optimization confinement performed. In particular, high- β N H-mode plasmas exhibiting an internal transport barrier have obtained (normalized pressure reached up to 3). Injection impurity improved confinement. ELM using resonance magnetic perturbation or injection a...
Scenarios of steady-state, fully non-inductive current in Tore Supra are predicted using a package simulation codes (CRONOS). The plasma equilibrium and transport consistently calculated with the deposition power. achievement high injected energy discharges up to 1 GJ is shown. Two main scenarios considered: low density regime 90% driven by lower hybrid waves—lower drive (LHCD)—and combining LHCD ion cyclotron resonance heating bootstrap fraction 25%. predictive simulations existing also reported.
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...
A new tomography dedicated to detailed studies of the fast electron bremsstrahlung emission in hard x-ray (HXR) energy range between 20 and 200 keV during lower hybrid (LH) current drive experiments on TORE SUPRA tokamak [Equipe SUPRA, Proceedings 15th Conference Plasma Physics Controlled Nuclear Fusion Research, Seville (International Atomic Energy Agency, Vienna, 1995), Vol. 1, AIEA-CN-60 / A1-5, p. 105] is presented. Radiation detection performed by cadmium telluride semiconductors, which...
The role played by electron density fluctuations near the plasma edge on rf current drive in tokamaks is assessed quantitatively. For this purpose, a general framework for incorporating existing modelling tools has been developed. It valid when power absorption takes place far from fluctuating region of plasma. ray-tracing formalism modified order to take into account time-dependent perturbations density, while Fokker–Planck solver remains unchanged. evolution distribution function time and...
A new ray-tracing code named C3PO has been developed to study the propagation of arbitrary electromagnetic radio-frequency (rf) waves in magnetized toroidal plasmas. Its structure is designed for maximum flexibility regarding choice coordinate system and dielectric model. The versatility this makes it particularly suitable integrated modeling systems. Using a that reflects nested magnetic flux surfaces tokamaks, fast accurate calculations inside plasma separatrix can be performed using...
A detailed study of lower hybrid current drive (LHCD) in ITER is provided, focusing on the wave propagation and mechanisms. combination ray-tracing Fokker–Planck calculations are presented for various plasma scenarios, frequency polarization. The dependence driven location power deposition upon coupled spectrum systematically determined, order to set objectives antenna design. respective effects finite-power levels, magnetic trapping, spectra accounted quantitatively estimated. sensitivity...
A 4.6 GHz lower-hybrid current drive (LHCD) system has been firstly commissioned in EAST the 2014 campaign. The first LHCD results with show that LHW can be coupled to plasma a low reflection coefficient, and rotation, modify profile, heat effectively. By means of configuration optimization local gas puffing near antenna, good LHW–plasma coupling coefficient less than 5% is obtained. maximum power up 3.5 MW. (CD) efficiency 1.1 × 1019 m−2 W−1 central electron temperature above 4 keV,...
Recent experiments on EAST have achieved the first long pulse H-mode (61 s) with zero loop voltage and an ITER-like tungsten divertor, demonstrated access to broad plasma current profiles by increasing density in fully-noninductive lower hybrid current-driven discharges. These discharges reach wall thermal particle balance, exhibit stationary good confinement (H98y2 ~ 1.1) low core electron transport, are only possible optimal active cooling of armors. In separate experiments, was...
Runaway electrons are generated in a magnetized plasma when the parallel electric field exceeds critical value. For such with energies typically reaching tens of MeV, Abraham–Lorentz–Dirac (ALD) radiation force, reaction to synchrotron emission, is significant and can be dominant process limiting electron acceleration. The effect ALD force on runaway dynamics homogeneous investigated using relativistic finite-difference Fokker–Planck codes LUKE (Decker Peysson 2004 Report EUR-CEA-FC-1736,...
Abstract A new record was set on the WEST Tokamak, designed to operate long duration plasmas in a tungsten (W) environment, with an injected energy of 1.15 GJ and plasma 364 s. Scenario development supported by integrated modeling using High Fidelity Plasma Simulator (HFPS), European IMAS-coupled version JETTO/JINTRAC, which integrates physics-driven modules into unified framework. In particular, reduced model for Lower-Hybrid heating Current-Drive (LHCD) quasi-linear turbulent transport...
The ITER Scenario Modelling Working Group (ISM WG) is organized within the European Task Force on Integrated Tokamak (ITM-TF). main responsibility of WG to advance a pan-European approach integrated predictive modelling plasmas with emphasis urgent issues, identified during Design Review. Three major topics are discussed, which considered as and where has best possible expertize. These current profile control, density control impurity in (the last two involve both core SOL plasma). Different...
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...
Aimed at high-confinement (H-mode) plasmas in the Experimental Advanced Superconducting Tokamak (EAST), effect of local gas puffing from electron and ion sides a lower hybrid wave (LHW) antenna on LHW–plasma coupling high-density experiments with current drive (LHCD) are investigated EAST. results show that side is more favourable to improve compared side. Investigations indicate without affected by density near LHW grill (grill density), hence leading multi-transition low–high–low (L–H–L)...
Runaway electrons can be generated in tokamak plasmas if the accelerating force from toroidal electric field exceeds collisional drag owing to Coulomb collisions with background plasma. In ITER, disruptions are expected generate runaway mainly through knock-on (Hender et al 2007 Nucl. Fusion 47 S128–202), where enough momentum transferred existing runaways slow transport latter beyond a critical momentum, setting off an avalanche of electrons. Since usually scattered significant...
Radio-frequency (rf) waves are a powerful tool for improving the performance and stability of tokamak plasmas through heating current drive mechanisms, allowing density profile control steady-state operation. From first principles, taking advantage from ordering between various time space scales, fast numerical tools have been developed to calculate rf-driven current. The problem in tokamaks is introduced with purpose maintaining self-organized toroidal magnetohydrodynamic equilibrium, such...
First principle modeling of the lower hybrid (LH) current drive in tokamak plasmas is a longstanding activity, which gradually gaining accuracy thanks to quantitative comparisons with experimental observations. The ability reproduce simulatenously plasma and non-thermal bremsstrahlung radial profiles hard x-ray (HXR) photon energy range represents this context significant achievement. Though subject limitations, ray tracing calculations are commonly used for describing wave propagation...
EAST has been equipped with two high power lower hybrid current drive (LHCD) systems operating frequencies of 2.45 GHz and 4.6 GHz. Comparative LHCD experiments the different were performed in same conditions plasma for first time. It was found that (CD) efficiency heating effect are much better LH waves than one High confinement mode (H-mode) discharges as sole auxiliary source have obtained is higher respect to produced previously by A combination ray-tracing Fokker-Planck calculations...
The mission of HL-2A is to explore the key physical topics relevant ITER and advanced tokamak operation (e.g. future HL-2M), such as access H-mode, energetic particle physics, edge-localized mode (ELM) mitigation/suppression disruption mitigation. Since 2016 Fusion Energy Conference, team has focused on investigations following areas: (i) pedestal dynamics L–H transition, (ii) techniques ELM control, (iii) turbulence transport, (iv) physics. results demonstrated that increase mean shear flow...
Abstract In the full tungsten environment of WEST, during its first phase operation, around 25% pulses exhibited a rapid central electron temperature collapse. phase, WEST plasmas were mostly heated by lower hybrid current drive (LHCD) and ion cyclotron resonance heating (ICRH). this publication, collapsing are analysed to understand key actuators at play. Experimentally, an initial slow reduction due density increase is observed, while profile flat constant in time. Then, radiative collapse...