Influence of hydrogen trapping on WCLL breeding blanket performances

Tritium transport simulations in Water-Cooled Lithium Lead (WCLL) breeding blankets have been performed with FESTIM. Fluid dynamics and heat transfer were coupled to evaluate how temperature and LiPb velocity fields affect Tritium transport. The 2D WCLL model consisted of tungsten, EUROFER and liquid LiPb. Tritium inventories and permeation fluxes have been computed and the influence of trapping effects in solid domains was highlighted. It was evaluated that inclusion of trapping mechanisms increases inventory values by 15\% and delays permeation to the cooling channels. A parametric study was conducted to investigate the impact of the uncertainty in the literature (2 orders of magnitude) regarding hydrogen solubility in LiPb on these quantities. Varying the lithium lead solubility over the range found in the literature was found to vary the EUROFER inventory by a factor of 25. Permeation fluxes to the coolant channels were found to vary over a factor of 3.