Integrated Modeling of Tokamak Plasmas

These simulations continue our efforts to understand the neoclassical prediction of the heat load on the divertor plates for the DIII-D and Alcator C-Mod discharges. In our previous studies with the anomalous transport included, we have found that the temperature of neutrals change the rate of the pedestal build up. However, the final pedestal profiles that were limited by the ideal stability conditions that were analyzed with the ELITE code are found independent of the neutral temperature. It turns out that the neoclassical case is different. Without additional dissipation from the anomalous transport, the plasma density profiles become too sharp just before the separatrix. After discussing this problem with Gunyoung, the initial temperature of neutrals have been reduced from 50 eV to 3 eV (Compton temperature). The plasma profiles looks more reasonable. However, there is still spiky in the ion temperature profile just after the seperatrix and there is a deep in the plasma
density profile in the separatrix region. The heat load profiles looks more realistic as well (except of the electron particle flux for the inner divertor plate). The results below are given for the DIII-D discharge 132016.03023 (case XGC-B35).