Impurity transport in ITG and TE mode dominated turbulence

The transport properties of impurities is of high relevance for the performance and optimisation of magnetic fusion devices. For instance, impurities from plasma-facing surfaces accumulating in the core dilute the plasma and lead to unacceptable energy loss in the form of radiation. In the present study, turbulent impurity transport in tokamak plasmas, driven by Ion Temperature Gradient (ITG) and Trapped Electron (TE) modes, is investigated using fluid and gyrokinetic models. Quasilinear (QL) results obtained from the GENE code are compared with fluid results for ITG and TE mode dominated turbulence. Scalings of the peaking factor with impurity charge (Z) and various parameters are studied. Of particular interest are conditions favouring an outward convective impurity flux