Global Gyrokinetic Multimodel Simulations of ITG and Alfvénic Modes for Tokamaks and the First Operational Phase of Wendelstein 7-X

Full text: Results from a hybrid approach (CKA-EUTERPE code) which couples an MHD code with a gyrokinetic code are presented. Although perturbative, it offers a relatively fast way to investigate the destabilization of Alfvén modes by fast particles. TAE saturation amplitudes and their scaling with growth rate and collisionality were investigated in a tokamak as well as in Wendelstein 7-X. Full volume linear electrostatic gyrokinetic simulations for an OP1.1 Wendelstein 7-X scenario showed modes driven by the strong electron temperature gradient with negligible influence from trapped particles. Using a Fourier solver approach, longtime fully kinetic runs of damped GAEs and TAEs could be performed. Super-resolution methods allowed accurately resolution of the the continuous Alfvén spectrum. (author)