Extending estimation of the critical deposition velocity in solid–liquid pipe flow to ideal and non-ideal particles at low and intermediate solid volume fractions

• Published in: Chemical engineering science Vol. 211; p. 115308
• Main Authors: Rice, Hugh P., Peakall, Jeffrey, Fairweather, Michael, Hunter, Timothy N.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 16.01.2020
• Subjects: Acoustic measurements; Particle-laden flow; Radioactive waste; Sediment transport; Ultrasonics; Radioactive waste; Acoustic measurements; Particle-laden flow; Ultrasonics; Sediment transport
• ISSN: 0009-2509; 1873-4405
• DOI: 10.1016/j.ces.2019.115308

•Critical deposition velocity separates suspended and bed-forming particle-laden flows.•Data from new experiments using acoustic method combined with data from literature.•Relationship found between critical deposition velocity and material/flow properties.•Volume factor accounts for non-ideal behaviour of solid particles such as aggregation.•Correlation found between volume factor and packing fraction of solid phase. The critical deposition velocity in horizontal pipe flow of liquid-solid slurries separates bed-forming and fully suspended flows. A compilation of critical deposition velocity data is presented using new experimental data (for particles ranging from 9 to 690 µm in diameter) along with data from the literature, and a close correlation between the particle Reynolds number and the Archimedes number (which describe the properties of the flow and the liquid and solid phases) is found. The role of solid particle packing is discussed and suggestions are made for the incorporation of solid-phase material properties – specifically particle shape and angularity, and surface forces – into an empirical parameter, the volume factor, α, to account for the deviation of particle behaviour from ideal, non-interacting, hard-sphere behaviour.