Use of power averaging for quantifying the influence of structure organization on permeability upscaling in on‐lattice networks under mean parallel flow

with the local permeability distribution variance s 2 is nonnegligible but remains small. It is equal to 0.09 for sparse networks and 0.14 for dense networks representing 4.5% and 7%, respectively, of the full possible range of w values. Power averaging is not strictly valid but gives an estimate of upscaling at a few percent. Here w depends slightly on the local permeability distribution shape beyond its variance but mostly on the morphological network structures. Most of the morphological control on upscaling for on‐lattice structures is local and topological and can be explained by the dependence on the average number of neighbor by points (effective coordination number) within the flowing structure (backbone).