Low Reynolds Number Flow in a Packed Bed of Rotated Bars

Abstract

The present study focuses on the gas flow through an experiment-scale modular packed-bed reactor consisting of square bars arranged in layers. Each layer is rotated by 30°, resulting in a complex shape of the void spaces. Particle image velocimetry measurement results inside and above the bed are presented for Reynolds numbers of 100 and 200 and used as validation data for two sets of particle-resolved numerical simulations, using a boundary-conforming meshing strategy and treating the solid boundaries via the blocked-off method. The flow inside the bed is largely independent of the Reynolds number and determined by the void space geometry. The flow in the freeboard is dominated by the presence of slowly dissipating jets downstream of the bed. The numerical results are in good agreement with the measurements, both inside and above the bed; however, stronger deviations can be observed in the freeboard and can be traced to numerical properties of the current simulation approaches.