Experiments and simulations of settling cylinders over a wide range of Archimedes numbers

Abstract

AbstractQuantitative visualization experiments and particle‐resolved simulations of rigid cylindrical particles settling in a Newtonian liquid have been conducted. By varying the viscosity of the liquid—a glycerol‐water mixture—as well as the density of the cylinders, we were able to cover an Archimedes number range that spans almost six orders of magnitude in the experiments. The length over diameter aspect ratio of the cylinders ranged from 2.5 to 20. Cylinders were released vertically and rotated to a stable horizontal orientation in most of the lower viscosity solutions. The time required for reaching a horizontal orientation, as well as the Reynolds number at that stage, scale with the Archimedes number and only weakly depend on the aspect ratio. Particle‐resolved numerical simulations based on the lattice‐Boltzmann method complement the experimental study and illustrate the relevance of the experimental data as a benchmark for numerical approaches to solid–liquid flow with non‐spherical particles.