A5076186300- Magnetic confinement fusion research
- Particle accelerators and beam dynamics
- Ionosphere and magnetosphere dynamics
- Superconducting Materials and Applications
- Fusion materials and technologies
- Laser-Plasma Interactions and Diagnostics
- Plasma Diagnostics and Applications
- Gyrotron and Vacuum Electronics Research
- Solar and Space Plasma Dynamics
- Nuclear Physics and Applications
- Electron and X-Ray Spectroscopy Techniques
- High-Energy Particle Collisions Research
- Earthquake and Tsunami Effects
- Dust and Plasma Wave Phenomena
- Numerical Methods and Algorithms
- Nuclear reactor physics and engineering
- Pulsed Power Technology Applications
- Fluid Dynamics and Turbulent Flows
- Agricultural Practices and Plant Genetics
- Fluid Dynamics and Vibration Analysis
- Target Tracking and Data Fusion in Sensor Networks
- Atomic and Subatomic Physics Research
- earthquake and tectonic studies
- Laser-induced spectroscopy and plasma
- Magneto-Optical Properties and Applications
Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement
2024
Biologie du Fruit et Pathologie
2022-2024
CEA Cadarache
2009-2021
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2009-2021
Institut de Recherche sur la Fusion par Confinement Magnétique
1996-2017
University of California, San Diego
2013
Korea Institute of Fusion Energy
2011
Culham Science Centre
2011
Institute for Plasma Research
2011
ITER
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...
Parametric scalings of the intrinsic (spontaneous, with no external momentum input) toroidal rotation observed on a large number tokamaks have been combined an eye towards revealing underlying mechanism(s) and extrapolation to future devices. The velocity has found increase plasma stored energy or pressure in JET, Alcator C-Mod, Tore Supra, DIII-D, JT-60U TCV, decrease increasing current some these cases. Use dimensionless parameters led roughly unified scaling MA ∝ βN, although variety Mach...
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...
This special topic describes the contents of an L mode database that has been compiled with data from Alcator C-Mod, ASDEX, DIII, DIII-D, FTU, JET, JFT-2M, JT-60, PBX-M, PDX, T-10, TEXTOR, TFTR and Tore Supra. The consists a total 2938 entries, 1881 which are in phase while 922 ohmically heated only (ohmic). Each entry contains up to 95 descriptive parameters, including global kinetic information, machine conditioning configuration. presents description variables contained therein, it also...
The experimental programme of Tore Supra, the largest superconducting tokamak in world (a = 0.72 m, R 2.4 Ip < 1.7 MA, BT 4.5 T) was devoted 2003 to studying heat removal capability and particle exhaust steady-state fully non-inductive current drive discharges simultaneously. This required both advanced technology integration real-time plasma control. In particular, an improvement position within a range few millimetres, new controls radio frequency power various actuators built around...
This paper presents the results of three-dimensional fluid global simulations electrostatic ion turbulence in tokamaks with reversed magnetic shear. It is found that a transport barrier appears at location shear reversal. due to rarefaction resonant surfaces this region. For same reason, more pronounced when minimum safety factor simple rational number. The broadened by velocity effects. also large-scale events hardly cross barrier. Finally, significant amount toroidal rotation generated...
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...
Electron transport in tokamaks has many different features which are briefly reviewed. The paper is focused on electron heat conventional tokamak plasmas. An inter-machine comparison indicates that the non-dimensional gradient length of temperature profiles R/LTe almost independent devices and varies little with plasma parameters. This strongly suggests governed by turbulence a threshold R/LTe. confirmed modulation experiments using cyclotron heating. Simulations empirical physics-based...
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.
In Tore Supra plasmas with fast wave electron heating, a critical threshold in the temperature gradient (inverted DeltaT(e)) is clearly observed, i.e., finite value of inverted DeltaT(e) for which turbulent heat diffusivity vanishes. The radial profile this experimentally determined from set discharges characterized by similar plasma parameters powers ranging 0.75 to 7.4 MW. dependence flux on length found be offset linearly. term increases linearly ratio local magnetic shear safety factor.
Anomalous transport in tokamaks is generally attributed to turbulent fluctuations. Since a large variety of modes are potentially unstable, wide range short-scale fluctuations should be measured, with wavenumbers from kρi ∼ 0.1 ≫ 1. In the Tore Supra tokamak, light scattering experiment has made possible fluctuation measurements medium- and high-k domains where transition k-spectrum observed: level decreases much faster than usual observations, typically power law S(k) ≡ k−6. A scan ion...
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...
Backscattering of a microwave beam close to the cut-off allows for measurement density fluctuations at specified wave-number, selected by scattering geometry , where ki is wave-number reflection layer. On Doppler reflectometry system installed on Tore Supra, both k⊥ and localization (r/a) can be changed during shot owing steppable probing frequency motorized antenna. Operating in O mode, spatial ranges depend essentially profile, typically 0.5 < r/a 0.95 2 k 15 cm−1. Wave number spectra are...
Turbulence measurements in TORE SUPRA tokamak plasmas have been quantitatively compared to predictions by nonlinear gyrokinetic simulations. For the first time, numerical results simultaneously match within experimental uncertainty (a) magnitude of effective heat diffusivity, (b) rms values density fluctuations, and (c) wave-number spectra both directions perpendicular magnetic field. Moreover, simulations help revise as an instrumental effect apparent evidence strong turbulence anisotropy...
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...
The entropy production rate is calculated for an interchange driven turbulence both in fluid and kinetic regimes. This calculation provides a rigorous way to define thermodynamical forces fluxes. It found that the are gradients of density temperature normalized their “canonical” values, which Lagrangian invariants flow. formulation equivalent expressing fluxes terms “curvature pinches,” where curvature pinches proportional logarithmic gradient canonical profiles. Off diagonal transport...
Recently, plasmas exceeding 4 min have been obtained with lower hybrid current drive (LHCD) in Tore Supra. These LHCD extend for over 80 times the resistive diffusion time zero loop voltage. Under such unique conditions neoclassical particle pinch driven by toroidal electric field vanishes. Nevertheless, density profile remains peaked more than min. For first time, existence of an inward steady-state plasma without field, much larger value predicted collisional theory, is experimentally demonstrated.
Results of stability analysis are presented for two types plasma with good confinement: internal transport barriers (ITBs) on Tore Supra and the radiative improved (RI) mode TEXTOR. The has been performed an electrostatic linear gyrokinetic code, evaluating growth rates microinstabilities. code developed, KINEZERO, is aimed at systematic microstability analysis. Therefore trade-off between having perfect quantitative agreement minimizing computation time made in favour latter. In plasmas...
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...
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...
The hot electron plasmas (Te&gt;2Ti) in Tore Supra (Equipe (presented by R. Aymar) Plasma Physics and Controlled Nuclear Fusion Research [Proc. 12th Int. Conf., Nice, 1988 (IAEA, Vienna, 1989), Vol. 1, p. 9]) driven fast wave heating (FWEH) are analyzed for thermal transport. Both neoclassical anomalous transport processes taken into account. dominant power flow is through the channel of diffusivity. ion temperature gradient instabilities a well documented discharge shown to explain...
This paper describes the updates to and analysis of International Tokamak Physics Activity (ITPA) Global H-Mode Confinement Database version 3 (DB3) over period 1994–2004. data, for energy confinement time its controlling parameters, have now been collected from 18 machines different sizes shapes: ASDEX, ASDEX Upgrade, C-Mod, COMPASS-D, DIII-D, JET, JFT-2M, JT-60U, MAST, NSTX, PBX-M, PDX, START, T-10, TCV, TdeV, TFTR TUMAN-3M. The database contains 10382 data entries 3762 plasma discharges,...
The effect of bulk ion heating in Tore Supra has been investigated by studying discharges with varying concentrations minority ions during ICRF hydrogen deuterium/4He plasmas. As expected, the level is found to increase concentration. Higher levels are shown be accompanied two significant effects: an improved energy confinement and a strong influence on plasma rotation.
The TORE SUPRA lower hybrid current drive experiments (8 MW/3.7 GHz) use large phased waveguide arrays, four rows of 32 active waveguides and two passive for each the grills, to couple waves plasma. These launchers are based on 'multijunction' principle which allows them be quite compact is therefore attractive design efficient multi-megawatt antennas in NET/ITER. Extensive coupling measurements have been performed order study radiofrequency (RF) characteristics plasma loaded antennas....