Whole Device Modelling of coupling between fixed gradient driven core delta-f and flux driven edge total-f gyrokinetic models with XGC.*

A Whole Device Model (WDM) for coupling core delta-f and edge total-f gyrokinetic models is presented as a tool for understanding and predicting the H-mode of ITER and other future fusion facilities. This model, which is implemented in a single XGC simulation, lets the gradient-driven E×B turbulence of the core flow into the edge region. The edge being modeled with the usual XGC flux driven total-f model. The new core delta-f model solves the same equations than the total-f model while using a different background definition (such as corrected canonical Maxwellian), which enables to keep a small δf ≪ f0 in the core by applying coarse-graining and thermal-bath procedures. The thermal bath fixes the averaged temperature profile while leaving the flux-surface averaged density and parallel momentum free to relax. We will discuss the convergence and numerical aspects of this new numerical scheme. Preliminary results of a core-edge whole-device model simulation will be presented.