Carbon transport in the ASDEX Upgrade outer divertor plasma is investigated in numerical simulations. The SOLPS5.0 code package is used to model the scrape-off layer plasma in a set of repeated lower-single-null L-mode discharges. Special emphasis is given to replicate the plasma conditions measured in the full tungsten, vertical outer target of ASDEX Upgrade, and solutions with and without the effect of drifts are presented. First ERO simulations of hydrocarbon transport in a SOLPS plasma background including drifts are carried out, and significantly closer match to the experimental 13C deposition pattern is obtained than with the solution without drifts. The 2D divertor electric field predicted by SOLPS is applied to the ERO modelling, and it is observed to result in a poloidal hydrocarbon drift that agrees well with the experiment. An increased carbon deposition efficiency, particularly upstream from the source, is obtained in the normal ASDEX Upgrade field configuration.
- Electric field
- Impurity transport