Publications de Olivier Sauter

Chattez avec Graph Search

Posez n’importe quelle question sur les cours, conférences, exercices, recherches, actualités, etc. de l’EPFL ou essayez les exemples de questions ci-dessous.

AVERTISSEMENT : Le chatbot Graph n'est pas programmé pour fournir des réponses explicites ou catégoriques à vos questions. Il transforme plutôt vos questions en demandes API qui sont distribuées aux différents services informatiques officiellement administrés par l'EPFL. Son but est uniquement de collecter et de recommander des références pertinentes à des contenus que vous pouvez explorer pour vous aider à répondre à vos questions.

Magnetohydrodynamic (MHD) equilibrium states with a three-dimensional helical core that display the characteristics of a saturated ideal internal kink mode are computed to model snake structures that have been observed in the JET tokamak [A.~Weller et al. ...

Current profile tailoring has been performed by application of electron cyclotron heating (ECH) and electron cyclotron current drive, leading to improved energy confinement in the plasma core of the TCV tokamak. The improved confinement is characterized by a substantial enhancement (H-factor) of the global electron energy confinement time relative to the prediction of the RLW scaling law (Rebut P H et al 1989 Proc. 12th Int. Conf. of Plasma Physics and Controlled Fusion Research (Nice, 1988) vol 2 (Vienna:

The ITER Integrated Modelling and Analysis System (IMAS) has been adopted by the EUROfusion Consortium as a platform to facilitate the analysis and verification of data from multiple tokamaks for the integration of physics codes and the validation of physi ...

Block-structured mesh generation techniques have been well addressed in the CFD community for automobile and aerospace studies, and their applicability to magnetic fusion is highly relevant, due to the complexity of the plasma-facing wall structures inside ...

The recent development of real-time measurements and control tools in JET has enhanced the reliability and reproducibility of the relevant ITER scenarios. Diagnostics such as charge exchange, interfero-polarimetry, electron cyclotron emission have been upgraded for real-time measurements. In addition, real-time processes like magnetic equilibrium and q profile reconstruction have been developed and applied successfully in real-time q profile control experiments using model based control techniques. Plasma o

Within the range of plasma shapes and plasma currents investigated, the electron confinement time, Tau_E increases with density, elongation and negative triangularity (-0.4

Developing successful tokamak operation scenarios, as well as confident extrapolation of present-day knowledge requires a rigorous understanding of plasma turbulence, which largely determines the quality of the confinement. In particular, accurate particle ...

The aim of this paper is to present a signal processing algorithm that, applied to the raw Locked Mode signal, allows us to obtain a disruption indicator in principle exploitable on different tokamaks. A common definition of such an indicator for different ...

ERO is a 3D Monte-Carlo impurity transport and plasma-surface interaction code. In 2011 it was applied for the ITER first wall (FW) life time predictions [1] (critical blanket module BM11). After that the same code was significantly improved during its app ...

A steady-state, fully noninductive plasma current has been sustained for the first time in a tokamak using electron cyclotron current drive only. In this discharge, 123 kA of current have been sustained for the entire gyrotron pulse duration of 2 s. Careful distribution across the plasma miner radius of the power deposited from three 0.5-MW gyrotrons was essential for reaching steady-state conditions. With central current drive, up to 153 kA of current have been fully replaced transiently for 100 ms. The no

Experimental observations in JET tokamak plasmas and gyrokinetic simulations point to an important role, for electron heat transport, of electron-scale instabilities and of their interaction with ion-scale instabilities. Since these effects are maximized f ...

The onset of a neoclassical tearing mode (NTM) depends on the existence of a large enough seed island. It is shown in the Joint European Torus that NTMs can be readily destabilized by long-period sawteeth, such as obtained by sawtooth stabilization from ion-cyclotron heating or current drive. This has important implications for burning plasma scenarios, as alpha particles strongly stabilize the sawteeth. It is also shown that, by adding heating and current drive just outside the inversion radius, sawteeth a

The development of a high current baseline scenario (I-p=3.5MA, q(95)approximate to 3.0, beta(N)

In 1970, Furth and Yoshikawa (1970 Phys. Fluids 13 2593-6) introduced the scalings of adiabatic plasma compression. Basically, if the shape of the external plasma boundary and the aspect ratio are preserved during the compression, then the density, kinetic ...

Progress in understanding lower hybrid current drive (LHCD) at high density has been made through experiments and modeling, which is encouraging given the need for an efficient off-axis current profile control technique in burning plasma. By reducing the w ...

Stability limits of highly elongated, D-shaped plasmas have been measured in the TCV (tokamak a configuration variable) tokamak. It is found that the plasma current is limited by kink-type disruptions, preceded by magnetohydrodynamic (MHD) mode activity. The mode structure has been analyzed using magnetic fluctuation and soft x-ray diagnostics. Mode numbers, growth rates, and experimental stability limits are consistent with ideal and resistive MHD models, based on measured plasma shapes and profiles. These

Clear evidence is reported for the first time of a rapid localized reduction of core electron energy diffusivity during the formation of an electron internal-transport barrier. The transition occurs rapidly (similar or equal to3 ms), during a slow (similar or equal to200 ms) self-inductive evolution of the magnetic shear. This crucial observation, and the correlation of the transition with the time and location of the magnetic shear reversal, lend support to models attributing the reduced transport to the l

For the first time, the JET operation in deuterium-tritium (D-T) plasma, which is scheduled to take place on JET in 2020, will be performed in the ITER mix of plasma-facing component materials. In view of the preparation of the DT campaign (DTE2), several ...

Low aspect ratio tokamaks (LATs) can potentially provide a high ratio of plasma pressure to magnetic pressure beta and high plasma current I at a modest size. This opens up the possibility of a high-power density compact fusion power plant. For the concept to be economically feasible, bootstrap current must be a major component of the plasma current, which requires operating at high beta(p). A high value of the Troyon factor beta(N) and strong shaping is required to allow simultaneous operation at a high-P

Real-time (RT) disruption prediction (DP) is essential to trigger mitigation actions that avoid irreversible damage to the devices. This paper deals with disruption mitigation alarms and performs the RT implementation of a probabilistic predictor. The RT i ...

Olivier Sauter

Chattez avec Graph Search

JET Snake Magnetohydrodynamic Equilibria

Control of electron internal transport barriers in TCV

Code Integration, Data Verification, and Models Validation Using the ITER Integrated Modeling and Analysis System (IMAS) in EUROfusion

A wall-aligned grid generator for non-linear simulations of MHD instabilities in tokamak plasmas

Integrated scenario in JET using real-time profile control

Preliminary Confinement Studies during ECRH in TCV

A new mechanism for increasing density peaking in tokamaks: improvement of the inward particle pinch with edge E x B shearing

A locked mode indicator for disruption prediction on JET and ASDEX upgrade

Improved ERO modelling of beryllium erosion at ITER upper first wall panel using JET-ILW and PISCES-B experience

Steady-state fully noninductive current driven by electron cyclotron waves in a magnetically confined plasma

Impact of electron-scale turbulence and multi-scale interactions in the JET tokamak

Control of neoclassical tearing modes by sawtooth control

Development of High-current Baseline Scenario for High Deuterium-tritium Fusion Performance at Jet

Shafranov shift correction to the Furth-Yoshikawa scaling of tokamak adiabatic compression

Review of recent experimental and modeling advances in the understanding of lower hybrid current drive in ITER-relevant regimes

Experimental and theoretical stability limits of highly elongated tokamak plasmas

Rapid and localized electron internal-transport-barrier formation during shear inversion in fully noninductive TCV discharges

The software and hardware architecture of the real-time protection of in-vessel components in JET-ILW

Stable equilibria for bootstrap-current-driven low aspect ratio tokamaks

Real-time implementation with FPGA-based DAQ system of a probabilistic disruption predictor from scratch