Gyrokinetic simulations of turbulent transport in JET-like plasmas

In this work turbulent transport in JET-like plasma discharges is analyzed, with main emphasis on impurity transport driven by ITG/TEM modes. Gyrokinetic (GK) simulations are performed using the GENE code [1, 2], in both quasilinear (QL) and nonlinear (NL) mode,1 and the results are compared with a computationally efficient fluid model [3, 4]. Particle transport is quantified by locally finding density gradients (R/Ln ) that yield zero particle flux, signifying a balance between convective and diffusive transport. The impact of the magnetic equilibrium (circular, s − α and realistic magnetic geometry) on the various models is discussed, as well as the effects of collisionality (in both fluid and GK) and the inclusion of a (2%) Carbon background (in GK), as per JET CFC wall conditions. The effect of sheared toroidal rotation was also investigated and found to be important, although not for the particular JET discharge studied in this work