The analytical solution can be calculated from the simple expression d2/32, with the channel width d = 20µm . The permeability computed with the flow solver depends strongly on the discretization of the no-slip boundary conditions. The no-slip boundary condition is discretized as described by Harlow-Welch (1965)1. A convergence study with increasing voxel resolution (from 2 to 64 voxel) shows that the numerical solution approaches the analytical permeability. Deviations below 2% are achieved with approximately 10 voxels.
