3D investigation and modeling of the geometric effects on porosity in packed beds

Abstract In porous beds, physical boundaries restrict particle arrangement, leading to inhomogeneous porosity. This paper reports on the porosity profiles that are the result of geometric effects on monodisperse packed beds in cylindrical and cubic arrangements. Special focus is given to the influence of edges and corners in cubic geometries. Three‐dimensional (3D) imaging results show that due to the arrangement of the spherical particles in corners and edges, where adjacent walls meet, maxima and minima in the porosity profile are more pronounced, and that peaks are less frequent than in systems with curved walls. For the porosity profile imposed by edges and corners, there are no notable global maxima or minima, but they show an increased bulk porosity, indicating anisotropic structural effects. To capture these geometric influences, a mathematical model based on an exponential approach is proposed, offering new insights for predicting porosity in systems bounded by both curved and planar walls.