(TH/P8-13) Global Electromagnetic Gyrofluid/Gyrokinetic Computation of Turbulence and Self Consistent Rotation in Large Tokamaks

B.D. Scott1), A. Bottino1), R. Hatzky1b), S. Jolliet2), A. Kendl3), B.F. Mcmillan2), D. Reiser4), T. Ribeiro5)
1) Max-Planck-IPP, Euratom Association, Garching, Germany
1b) Rechenzentrum der Max-Planck-Gesellschaft, Garching, Germany
2) CRPP, EPFL, Lausanne, Switzerland
3) Inst theor Physik, Euratom/OeAW, University of Innsbruck, Austria
4) Institut fuer Plasmaphysik, Euratom/FZ-Juelich, Juelich, Germany
5) IPFN, Euratom/IST, Lisbon, Portugal

Abstract.  We report on the theory and computation of gyrofluid and gyrokinetic turbulence in large tokamaks with special emphasis on the self consistent equilibrium including the poloidal rotation profile. The use of both gyrofluid and gyrokinetic models provides important control cases against the role of trapped electrons and ions. The models are necessarily global and electromagnetic, with strict energy and entropy conservation laws used as diagnostics. A control method for the particle weights in the PIC model provides correct thermodynamic saturation. A Hamiltonian discretisation scheme in the phase space continuum model provides correct long term nonlinear responses. For small tokamaks the turbulence can compete with neoclassical processes to determine the rotation profile but in large tokamaks the latter are dominant due to the comparative size scalings of the various processes. Edge turbulence is investigated with all the models, with regard to profile self consistency and also ELM scenarios. In all scenarios converged cases are found only if the spectrum reaches down to the ion gyroradius, so even the ELM scenario saturation is well outside the MHD regime.

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