Dynamic plasma-wall modeling of ELMy H-mode with UEDGE-MB-W

The results of time-dependent coupled simulations of the boundary plasma and the first wall deuterium inventory in various sequences of many type-I ELMs with UEDGE-MB-W code are presented. The temporal evolution of deuterium inventories of the pedestal plasma and wall and the calculated rates of particle deposition into the wall during ELMs and of wall outgassing between ELMs are compared to the experimental data on DIII-D. The fraction of pedestal particle losses deposited into the wall during ELMs is studied for different sizes and frequencies of ELMs. Modeling results for the discharge exhibiting the transition from small to giant type-I ELMs due to NBI heating decrease are discussed, demonstrating the important role of wall outgassing in the pedestal density built-up. The dynamic deposition/release equilibrium attained in the saturated wall in a sequence of ELMs and the roles of different plasma-material interaction processes in generating gas release are analyzed. (C) 2014 Elsevier B.V. All rights reserved.