Flows for magnetic fusion


The production of carbon-free energy by means of magnetic confinement fusion remains an ambitious scientific and technological challenge, which requires a long and sustained research effort. The construction of the ITER experimental reactor at Cadarache has accelerated our need to understand the mechanisms of transport and turbulence in plasma, and is driving the development of powerful simulation tools for successful fusion operation in the coming years.
The activities target the study of the fundamental mechanisms of transport and turbulence in tokamak plasmas under realistic conditions for the experiment. The main issue is the problem of power extraction under antagonistic operational conditions, i.e. a very hot and confined core and nevertheless heat extraction within the limits of the technological constraints related to the materials. Numerical developments must aim at reliable and predictive simulations both to prepare optimized discharge scenarios with all known constraints and to support the interpretation of experimental measurements. This research is based on fluid modeling for plasma quantities with the SOLedge3X family of codes developed for many years with the CEA-IRFM and kinetic modeling with the TAPAS code for the study of the trajectories of energetic particles produced during thermonuclear fusion reactions and which must remain confined to ensure a self-sustaining plasma.

Research topics

1.    Turbulent transport: Impact of the magnetic configuration on the transport and fluxes of matter and heat at the wall - Study of the transient phases of starting and stopping the machine - Transport of impurities at the plasma-wall interaction and impact on the fluxes - Edge-center coupling - Development of reduced models.
2.    Development and implementation of synthetic diagnostics and inference techniques: confrontation simulations / experiments - validation of codes.
3.    Physics of energetic particles: transport and losses of energetic particles in the presence of instabilities and turbulence
4.    Numerical developments: Implicit/explicit time schemes for hybrid discontinuous Galerkin methods - Meshes (aligned/disaligned, adaptive, ...) - Three-dimensional geometries - Code coupling (magnetic equilibrium/plasma code, plasma/neutral (EIRENE), plasma/impurities (ERO), ...)
5.   Development of metamodels for the quantification of uncertainties: construction either by methods of projection, dimension reduction and approximation in functional spaces or through more classical statistical models on spaces of reduced dimension. Application to the calculation of energetic particle trajectories in a first step.

Collaborations, Education and Valorization

Academic collaborations: CEA-IRFM; PIIM; I2M; University of Brittany: LPP, Magnetic Fusion Plasma team, Palaiseau (UMR 7648); Institut Jean Lamour, Physics of Matter and Materials team, Nancy (UMR 7198); LJAD (Nice); ITER; University Carlos III of Madrid, CIEMAT, Oak Ridge National Laboratory (USA).
Associated research and education structures: Master Fusion, ISFIN, National Fusion Federation, EUROfusion
Platforms (instrumental or digital): WEST tokamak, AMU mesocenter, GENCI

Ongoing projects: ANR SISTEM, ANR PLATUN, ANR AIM4EP, AMIDEX SAPHIR, EUROfusion Theory, Simulation, Validation and Verification projects 3 & 6, ....