TMAP-7 simulation of D2 thermal release data from Be co-deposited layers

The efficacy of (1) bake-out at 513 K and 623 K, and (2) thermal transient (10 ms) loading to up to 1000 K, is explored for reducing D inventory in 1 mu m thick Be-D (D/Be similar to 0.1) co-deposited layers formed at 323 K for experiment (1) and similar to 500 K for experiment (2). D release data from co-deposits are obtained by thermal desorption and used to validate a model input into the Tritium Migration & Analysis Program 7 (TMAP). In (1), good agreement with experiment is found for a TMAP model encorporating traps of activation energies, 0.80 eV and 0.98 eV, whereas an additional 2 eV trap was required to model experiment (2). Thermal release is found to be trap limited, but simulations are optimal when surface recombination is taken into account. Results suggest that thick built-up co-deposited layers will hinder ITER inventory control, and that bake periods (similar to 1 day) will be more effective in inventory reduction than transient thermal loading. (C) 2013 Elsevier B.V. All rights reserved.