Assessing the wall effects of packed concentric cylinders and angular walls on granular bed porosity

Abstract

The effect of added wall support on granular bed porosity is systematically studied to elucidate performance enhancements in filtration processes achieved by using inserts, as demonstrated experimentally (Bandelt Riess et al. in Chem Eng Technol 2018, 2021). Packed beds of spheres are simulated through discrete element method in cylinders with different internal wall configurations. Three containing systems are generated: concentric cylinders, angular walls, and a combination of both. Variations of particle size and wall friction and thickness are also considered, and the resulting granular bed porosities are analyzed. The porosity increase is proportional to the incorporated wall support; the combination of cylindrical and angular inserts displays the greatest effect (up to 26% increase). The sinusoidal porosity values near the walls are exhibited to clarify the effects. The presented method can change and evaluate granular bed porosity increments, which could lead to filtration process improvements, and the obtained behaviors and profiles can be used to explore additional effects and further systems. Graphical abstract

Structure and flow conditions through a colloidal packed bed formed under flow and confinement

“…the number of particle layers along the channel height is too small to neglect the contribution of the flow near the channel surface. [56][57][58][59] Secondly, because of the heterogeneous microstructure 60,61 of the accumulation with the presence of void zones, 44,57,62 which inevitably favours an heterogeneous flow through the porous structure. We also observed that when we get closer to the CCC, at I = 100 mM, the value of f remains unchanged (Fig.…”