Influence of curved struts, anisotropic pores and strut cavities on the effective elastic properties of open-cell foams

• We point out the importance of geometric details of foam models for simulations.
• Our models avoid sharp edges and include cavities, curved struts and pore anisotropy.
• The model type and details have an high impact on effective elastic foam properties.

This work focuses on the modelling of the local foam geometry (strut and node) and analyses its influence on the effective elastic properties. A periodic Kelvin cell is used as a simplified open cell structure. This allows detailed studies of often neglected local geometric details like strut thickness variations, strut curvature, node thickness, node and strut cavities. The foam geometry is described using implicit functions in Blinn transformations, which is a versatile modelling method leading to detailed finite element models. The finite element method together with a computational homogenisation technique is used to determine the effective elastic properties. These are presented for Kelvin cells having a constant porosity, but varying strut curvature and cross-section shape. Geometrical anisotropy and cavities in the struts and nodes are considered as well.