A5059558666- Magnetic confinement fusion research
- Ionosphere and magnetosphere dynamics
- Laser-Plasma Interactions and Diagnostics
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Parallel Computing and Optimization Techniques
- Advanced Data Storage Technologies
- Solar and Space Plasma Dynamics
- Distributed and Parallel Computing Systems
- Gas Dynamics and Kinetic Theory
- Fusion materials and technologies
- Plasma Diagnostics and Applications
- Fluid Dynamics and Turbulent Flows
- Parasite Biology and Host Interactions
- Computational Fluid Dynamics and Aerodynamics
- Nuclear reactor physics and engineering
- Advanced Numerical Methods in Computational Mathematics
- High-pressure geophysics and materials
- Seismic Imaging and Inversion Techniques
- Adhesion, Friction, and Surface Interactions
- Methane Hydrates and Related Phenomena
- Radiation Effects in Electronics
- Scientific Computing and Data Management
- Quantum chaos and dynamical systems
- Advanced Numerical Analysis Techniques
CEA Cadarache
2016-2025
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2015-2024
CEA Paris-Saclay
2017-2024
CEA Grenoble
2019-2024
Institut de Recherche sur la Fusion par Confinement Magnétique
2010-2019
Centre National de la Recherche Scientifique
1999-2017
Maison de la Simulation
2017
Université de Versailles Saint-Quentin-en-Yvelines
2017
Université Paris-Saclay
2017
Université Paris-Sud
2017
JOREK is a massively parallel fully implicit non-linear extended MHD code for realistic tokamak X-point plasmas. It has become widely used versatile studying large-scale plasma instabilities and their control developed in an international community. This article gives comprehensive overview of the physics models implemented, numerical methods applied solving equations studies performed with code. A dedicated section highlights some verification work done hierarchy different available...
Turbulence in hot magnetized plasmas is shown to generate permeable localized transport barriers that globally organize into the so-called "ExB staircase" [G. Dif-Pradalier et al., Phys. Rev. E, 82, 025401(R) (2010)]. Its domain of existence and dependence with key plasma parameters discussed theoretically. Based on these predictions, staircases are observed experimentally Tore Supra tokamak by means high-resolution fast-sweeping X-mode reflectometry. This observation strongly emphasizes...
The interaction of static Resonant Magnetic Perturbations (RMPs) with the plasma flows is modeled in toroidal geometry, using non-linear resistive MHD code JOREK, which includes X-point and scrape-off-layer. Two-fluid diamagnetic effects, neoclassical poloidal friction a source rotation are introduced model to describe realistic flows. RMP penetration studied taking self-consistently into account effects these radial electric field evolution. JET-like, MAST, ITER parameters used modeling....
The turbulent transport governed by the toroidal ion temperature gradient driven instability is analysed with full- f global gyrokinetic code GYSELA (Grandgirard et al 2007 Plasma Phys. Control. Fusion 49 B173 ) when system a prescribed heat source. Weak, yet finite, collisionality governs neoclassical flux that can compete transport. In turn, ratio of to increases source magnitude, resulting in degradation confinement additional power. exhibits avalanche-like events, characterized...
The impact on turbulent transport of geodesic acoustic modes excited by energetic particles is evidenced for the first time in flux-driven 5D gyrokinetic simulations using Gysela code. Energetic (EGAMs) are a regime with barrier outer radial region. interaction between EGAMs and turbulence such that can be enhanced presence EGAMs, subsequent destruction barrier. This scenario could particularly critical those plasmas, as burning exhibiting rich population suprathermal capable exciting modes.
A possible mechanism of edge localized modes (ELMs) mitigation by resonant magnetic perturbations (RMPs) is proposed based on the results nonlinear resistive magnetohydrodynamic modeling using jorek code, realistic JET-like plasma parameters and an RMP spectrum JET error-field correction coils (EFCC) with a main toroidal number n=2 were used in simulations. Without RMPs, large ELM relaxation obtained mainly due to most unstable medium-n ballooning mode. The externally imposed drives...
We show that a class of near-marginal and low-collisional magnetised plasmas naturally evolve into globally organised state dubbed the ' × E B staircase'.A key signature this self-organised is containment avalanche activity, detrimental for confinement, by series microbarriers transport, staircase steps, beneficial confinement.Conditions existence staircase, impact on transport confinement robustness in parameter space are discussed.
Critical physical issues can be specifically tackled with the global full-f gyrokinetic code GYSELA. Three main results are presented. First, self-consistent treatment of equilibrium and fluctuations highlights competition between two compensation mechanisms for curvature driven vertical charge separation, namely, parallel flow polarization. The impact latter on turbulent transport is discussed. In non-linear regime, benchmark Particle-In-Cell ORB5 looks satisfactory. Second, scaling ρ*...
We have designed a fast parallel simulator that solves the acoustic wave equation on GPU cluster. Solving in an oil exploration industrial context aims at speeding up seismic modeling and Reverse Time Migration. consider finite difference approach regular mesh, both 2D 3D cases. The is solved either constant density or variable domain. All computations are done single precision, since double precision not required our context. use CUDA to take advantage of GPUs computational power. study...
Flux-driven global gyrokinetic codes are now mature enough to make predictions in terms of turbulence and transport tokamak plasmas. Some the recent breakthroughs three such codes, namely GYSELA, ORB5 XGC1, reported compared wherever appropriate. In all turbulent appears be mediated by avalanche-like events, for a broad range ρ * = i / values, ratio gyro-radius over minor radius. Still, radial correlation length scales with , leading gyro-Bohm scaling effective coefficient below ≈ 1/300. The...
Conservation equations are derived for the gyrocenter toroidal momentum density and polarization field. These from gyrokinetic model as it is implemented in simulation codes. In view of predicting rotation future fusion devices such ITER, where external input will be small, accurate simulations transport crucial. The evolution equation involves divergence off-diagonal components Reynolds generalized Maxwell stress, while source term radial current gyrocenters. time field opposite current....
Treatment of binary Coulomb collisions when the full gyrokinetic distribution function is evolved discussed here. A spectrum different collision operators presented, differing through both physics that can be addressed and numerics they are based on. Eulerian-like (semi-Lagrangian) particle in cell (PIC) (Monte-Carlo) schemes successfully cross-compared, a detailed confrontation to neoclassical theory shown.
It is shown that turbulence responsible for a source of momentum, which cannot be recast as divergence momentum flux. This process similar to turbulent heating, with properties. The sum over all species vanishes up polarization contributions. Hence, toroidal transferred from species, mediated by turbulence. As flux, symmetry breaking needed. Flow shear investigated breaking, leading proportional the rate. Turbulent acceleration significant ion species. found it charge number Z, while heating...
The full dynamics of a multi-edge-localized-mode (ELM) cycle is modeled for the first time in realistic tokamak $X$-point geometry with nonlinear reduced MHD code jorek. diamagnetic rotation found to be instrumental stabilize plasma after an ELM crash and model cyclic reconstruction collapse pressure profile. relaxations are cyclically initiated each pedestal gradient crosses triggering threshold. Diamagnetic drifts also yield near-symmetric power deposition on inner outer divertor target...
Abstract Global, heat flux-driven ITG gyrokinetic simulations which manifest the formation of macroscopic, mean toroidal flow profiles with peak thermal Mach number 0.05, are reported. Both a particle-in-cell (XGC1p) and semi-Lagrangian (G YSELA ) approach utilized without priori assumptions scale separation between turbulence fields. Flux-driven different edge boundary conditions show in both approaches development net unidirectional intrinsic rotation co-current direction. Intrinsic torque...