FFT-based bounds on the permeability of complex microstructures

A numerical scheme for the computation of the permeability of complex microstructures is presented. As a darcean counterpart of the FFT-based scheme in elasticity, the method is designed to be directly coupled with 3D imaging techniques of porous samples, without meshing or definition of an equivalent pore network. The method relies on the variational principle of Hashin and Shtrikman, which ensures a rigorous upper bound status to the estimated permeabilities and provides an energetically consistent rule for heterogeneous voxels comprising both the solid and fluid phases. Copyright (c) 2014 John Wiley & Sons, Ltd.