Deep insights into fluid flow structures in Raschig ring packed beds via particle‐resolved CFD–DEM

Abstract Raschig rings are typically tubular in shape and are widely seen in packed beds across diverse chemical and thermal engineering processes. Owing to their intricate geometry and packing arrangement, the internal flow and fluid–solid interactions remain poorly understood. This study employs particle‐resolved computational fluid dynamics (PR‐CFD) coupled with the discrete element method (PR‐CFD–DEM) to investigate these phenomena with unprecedented numerical resolution. The PR‐CFD–DEM integrates a glued‐sphere DEM model and a workflow for extracting particle‐scale variables. The results show that the orientation of the Raschig ring, which is mainly governed by its length, together with its wall thickness, strongly affects the fluid velocity distribution, as well as the fluid–ring interaction forces. Moreover, the fluid tends to flow preferentially through the interstitial spaces instead of the inner channel regions of the rings. The findings offer deep insights into the fluid flow mechanisms governing Raschig ring packed‐bed systems.