Global gyrokinetic simulations of ASDEX Upgrade up to the transport time-scale with GENE-Tango

Abstract

An accurate description of turbulence up to the transport time scale is essential for predicting core plasma profiles and enabling reliable calculations for designing advanced scenarios and future devices. Here, we exploit the gap separation between turbulence and transport time scales and couple the global gyrokinetic code GENE to the transport-solver Tango, including kinetic electrons, collisions, realistic geometries, toroidal rotation and electromagnetic effects for the first time. This approach overcomes gyrokinetic codes' limitations and enables high-fidelity profile calculations in experimentally relevant plasma conditions, significantly reducing the computational cost. We present numerical results of GENE-Tango for two ASDEX Upgrade discharges, one of which exhibits a pronounced peaking of the ion temperature profile not reproduced by TGLF-ASTRA. We show that GENE-Tango can correctly capture the ion temperature peaking observed in the experiment. By retaining different physical effects in the GENE simulations, e.g., collisions, toroidal rotation and electromagnetic effects, we demonstrate that the ion temperature profile's peaking is due to electromagnetic effects of submarginal MHD instability. Based on these results, the expected GENE-Tango speedup for the ITER standard scenario is larger than two orders of magnitude compared to a single gyrokinetic simulation up to the transport time scale, possibly making first-principles ITER simulations feasible on current computing resources.

References in corpus (10)

• Nonlinear stabilization of tokamak microturbulence by fast ions
• Gyrokinetic projection of the divertor heat-flux width from present tokamaks to ITER
• Multiscale Gyrokinetics for Rotating Tokamak Plasmas: Fluctuations, Transport and Energy Flows
• Direct multiscale coupling of a transport code to gyrokinetic turbulence codes
• Electromagnetic turbulence suppression by energetic particle driven modes
• Tractable flux-driven temperature, density, and rotation profile evolution with the quasilinear gyrokinetic transport model QuaLiKiz
• New high-confinement regime with fast ions in the core of fusion plasmas
• Non-Maxwellian fast particle effects in gyrokinetic GENE simulations
• Bringing global gyrokinetic turbulence simulations to the transport timescale using a multiscale approach
• Investigation of a Multiple-Timescale Turbulence-Transport Coupling Method in the Presence of Random Fluctuations

Cited by in corpus (4)

• First-principles based plasma profile predictions for optimized stellarators
• Predictions of improved confinement in SPARC via energetic particle turbulence stabilization
• A quasi-linear model of electromagnetic turbulent transport and its application to flux-driven transport predictions for STEP
• The impact of plasma turbulence on atomic reaction rates in the detached ASDEX Upgrade divertor