Coupled two-dimensional edge-plasma and neutral gas modelling of the DIII-D scrape-off-layer

In order to do consistent scrape-off-layer plasma and neutral transport calculations, the 2D fluid code B2 has been externally coupled to the neutral transport code DEGAS for DIII-D. The coupling procedure is similar to simulations done for TFTR (Tokamak Fusion Test Reactor), Tore Supra, and CIT (Compact Ignition Tokamak). An `average´ source approach is utilized to allow convergence between the two codes. Initial comparison of plasma quantities between the coupled code set and the B2 code alone shows that a colder, denser plasma may exist at the divertor targets than predicted by the B2 code with its internal recycling model