Comparison of kinetic and fluid models for tungsten impurity transport using IMPGYRO and SOLPS

A benchmark calculation of tungsten impurity transport comparing kinetic modeling with IMPGYRO and multi-fluid modeling with SOLPS has been performed. The primary source of tungsten has been set at the outer mid-plane in the calculations. In both cases, impurity densities are relatively large in the SOL region near the top of the machine (top-SOL) compared to the divertor region mainly due to the effect of the thermal force. In the outer divertor region, however, a significant difference between the two codes has been observed, which could be explained by the effect of the drifts. The drifts are switched off in SOLPS in this study, while they are naturally taken into account in IMPGYRO. The drifts prevent impurities from being transported toward the outer divertor region.