Modelling of Pd-membranes deformation during hydrogen separation

Pd-membranes used for hydrogen separation work at elevated temperatures under pressure causing plastic deformation of the membranes. The problem is complicated by the fact that these membranes are very thin. Preferable thickness varies between 1 and 5μm. Different mathematical approaches can be used for modelling of this complex situation. Variety of 2D and 3D ABAQUS models are tested for this purpose. To simulate interface between the membrane and substrate, some models include contact analysis. Results from different models have been compared. The 2D-axisymmetric model is recommended for further inverse modelling due to its robustness and appropriate approximation of the real phenomenon. This model takes into account the through-thickness distribution of the stress-strain fields which in its turn is important for the accurate prediction of the membrane deformation under pressure.