Microstructure based model for permeability predictions of open-cell metallic foams via homogenization

To predict effective permeabilities of open-cell foams, produced by a SlipReactionFoamSintering (SRFS)-process, a multi-scale approach based on the homogenization method is applied. This formulation allows to calculate effective Darcy permeabilities by solving special Stokes flow problems on a unit cell. Starting from a detailed foam description by tomographic images, a new procedure based on a spectral analysis of the foam microstructure is presented in order to derive symmetric and non-symmetric unit cell models of the foam. Effective permeabilities are determined by using these unit cell models for a representative iron-based SlipReaction (SR)-foam sample. The analysis of these predictions leads to define one, rather simple, unit cell model suitable for further stochastic homogenization simulations.