Poloidal Distribution of Recycling Sources and Core Plasma Fueling in DIII-D, ASDEX-Upgrade, and JET L-mode Plasmas
Deuterium fueling profiles across the separatrix have been calculated with the edge fluid codes UEDGE, SOLPS, and EDGE2D/EIRENE for lower single null, ohmic and low-confinement plasmas in DIII-D, ASDEX Upgrade, and JET. The fueling profiles generally peak near the divertor x-point, and broader profiles are predicted for the open divertor geometry and horizontal targets in DIII-D than for the more closed geometries and vertical targets in AUG and JET. Significant fueling from the low field side midplane may also occur when assuming strong radial ion transport in the far scrape-off layer. The dependence of the fueling profiles on upstream density is investigated for all three devices, and between the different codes for a single device. The validity of the predictions is assessed for the DIII-D configuration by comparing the measured ion current to the main chamber walls at the low field side and divertor targets, and deuterium emission profiles across the divertor legs, and the high field and low field side midplane regions to those calculated by UEDGE and SOLPS.