Effect of particle orientation on the drag force in random arrays of oblate ellipsoids in <scp>low‐Reynolds</scp>‐number flows
Xinyang Li, Ming Jiang, Zheqing Huang, Qiang Zhou
Abstract
Abstract Through particle‐resolved direct numerical simulations of flows past random arrays of oblate ellipsoids at low Reynolds numbers, this work demonstrates how the drag force on oblate ellipsoids depends on the Hermans orientation factor S , the mean crosswise sphericity φ ⊥ , the aspect ratio AR , and the solid volume fraction c . Wide ranges of S , AR , and c are considered and they are in the intervals (−0.5, 1), (0.2, 0.8), and (0.1, 0.4), respectively. This study extends the work on prolate ellipsoids by Li et al (AIChE Journal, 2019, 65, e16621). Based on the simulation results, two models are respectively developed using S and φ ⊥ as the independent orientation factor. The model based on S could give accurate prediction of the drag force and the lateral force exerted on arrays of particles. The model based on φ ⊥ is able to use one generalized drag correlation for both oblate and prolate ellipsoids.