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Wave trapping and <i>E</i> × <i>B</i> staircases

A model of E × B staircases is proposed based on a wave kinetic equation coupled to poloidal momentum equation. staircase pattern idealized as periodic radial structure zonal shear layers that bound regions propagating packets, viewed avalanches. …

Gyrokinetic modelling of light to heavy impurity transport in tokamaks

Abstract Impurity transport is numerically investigated for different types of impurity, such as helium (He), argon (Ar), and tungsten (W). Both turbulent neoclassical transports are treated self-consistently using the full- f gyrokinetic software …

Overlapping communications in gyrokinetic codes on accelerator-based platforms

Summary Communication and computation overlapping techniques have been introduced in the five-dimensional gyrokinetic codes GYSELA GKV. In order to anticipate some of exa-scale requirements, these were ported modern accelerators, Xeon Phi KNL Tesla P …

Synergy of turbulent and neoclassical transport through poloidal convective cells

The role of poloidal convective cells—i.e. low frequency axisymmetric modes the electric potential—on transport processes is studied with full-F gyrokinetic code GYSELA. In order to understand impact cells, we apply a numerical filter cells and …

Neoclassical impurity flux in presence of turbulent generated poloidal asymmetries and pressure anisotropy

Poloidal asymmetries of impurities are commonly observed experimentally. Density asymmetry is already known to impact significantly the neoclassical prediction impurity fluxes. In this article, effect pressure and anisotropy on flux derived …

Immersed boundary conditions in global, flux-driven, gyrokinetic simulations

A penalization technique is applied in global and flux driven gyrokinetic simulations to model a limiter configuration. The immersed boundary implemented terms of restoring force cold distribution function. It acts as perfect heat absorber. Parallel …

Contribution of kinetic electrons to GAM damping

An approach to increase reliability of HPC simulation, application to the GYSELA5D code

Optimization of the gyroaverage operator based on Hermite interpolation

An asynchronous writing method for restart files in the GYSELA code in prevision of exascale systems