Particle-resolved CFD simulation of fixed bed pressure drop at moderate to high Reynolds number

Particle-resolved computational fluid dynamics simulations of flow and pressure drop in fixed beds of spheres give poor accuracy at higher Reynolds number (Re) under turbulent conditions. The influence of meshing is investigated for two cases, a face centered cubic packing with no wall effects, and a narrow bed of tube to-particle diameter ratio three with strong wall effects. Local approaches to meshing at contact points were compared, using both surface flattening (caps) and bridging between spheres. Accurate results for pressure drop at moderate to high Re > 1000 required computationally expensive fine uniform meshes, however at highest Re pressure drop appeared to be low. The use of boundary adaption improved results with less expensive meshes. The aspect ratio of surface prisms and the sizes of the bridges used at contact points had strong effects. Velocity profiles were much less sensitive to the mesh refinement and could be obtained at reasonable cost. ? 2021 Elsevier B.V. All rights reserved.

Automated summary

Particle-resolved computational fluid dynamics simulations in fixed beds of spheres show poor accuracy at higher Reynolds number under turbulent conditions. Different meshing techniques and boundary adaption can improve results and reduce cost. Accuracy for pressure drop requires computationally expensive fine uniform meshes, but velocity profiles are less sensitive to mesh refinement and can be obtained at reasonable cost.