Zhao, YL, Wang, Y, Yao, J et al. (1 more author) (2018) Reynolds number dependence of particle resuspension in turbulent duct flows. Chemical Engineering Science, 187 (1). pp. 33-51. ISSN 0009-2509
Abstract
Particle resuspension in a fully developed turbulent square duct flow is simulated using one-way coupled large eddy simulation coupled with a Lagrangian particle tracking technique for a range of bulk Reynolds numbers (36.5 k, 83 k and 250 k) and four particle sizes ranging from 5 to 500 μm (St = 0.01–2415) considered. Results obtained for the single-phase flow show good agreement with experimental data. Predictions of the time-dependent particle-laden flows demonstrate that the secondary flow mainly dominates particle resuspension in the regions near the center and sidewalls of the duct. It is found that particle resuspension decreases with particle size. The smaller particles tend to be more prone to resuspension, and are resuspended for a longer duration than larger particles. The mean particle resuspension velocity is found to increase with the duct height. In addition, particle resuspension in the vertical direction increases with Reynolds number while the effect of particle size on particle resuspension decreases. The resuspension rate in the spanwise direction fluctuates more as the Reynolds number increases. It is also found that the average particle resuspension rate in the lower half of the duct is always close to 0.5, and is independent of time, particle size and Reynolds number. Based on a dynamic analysis, the drag force is found to dominate the resuspension of small particles, while the lift force tends to dominate particle resuspension with increasing particle size. For low Reynolds number (36.5 k and 83 k) flows, the drag force plays an important role in the upper regions of the lower half of the duct, but the lift force dominates particle behavior in the lower regions. It can be concluded that the effects of duct height on particle behavior decline significantly with Reynolds number.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | (c) 2018 Elsevier Ltd. All rights reserved. This is an author produced version of a paper published in Chemical Engineering Science. Uploaded in accordance with the publisher's self-archiving policy |
Keywords: | Particle resuspension; Turbulence; Reynolds number; Duct flow; Secondary flow |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Chemical & Process Engineering (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 04 May 2018 08:52 |
Last Modified: | 26 Apr 2019 00:39 |
Status: | Published |
Publisher: | Elsevier |
Identification Number: | 10.1016/j.ces.2018.04.053 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:130415 |