RESUMO
Helium diffusion, clustering and bubble nucleation and growth is modelled using the finite element method. The existing model from Faney et al. (Model Simul Mater Sci Eng 22:065010, 2018; Nucl Fusion 55:013014, 2015) is implemented with FEniCS and simplified in order to greatly reduce the number of equations. A parametric study is performed to investigate the influence of exposure conditions on helium inventory, bubbles density and size. Temperature is varied from 120 K to 1200 K and the implanted flux of 100 eV He is varied from [Formula: see text] to [Formula: see text]. Bubble mean size increases as a power law of time whereas the bubble density reaches a maximum. The maximum He content in bubbles was approximately [Formula: see text] He at [Formula: see text]. After 1 h of exposure, the helium inventory varies from [Formula: see text] at low flux and high temperature to [Formula: see text] at high flux and low temperature. The bubbles inventory varies from [Formula: see text] bubbles m[Formula: see text] to [Formula: see text] bubbles m[Formula: see text]. Comparison with experimental measurements is performed. The bubble density simulated by the model is in quantitative agreement with experiments.
