Threshold Criteria for Components of Predictive Model for Pipe Flow of Broadly-Graded Slurry
2018 (English)In: ASME 2018 5th Joint US-European Fluids Engineering Division Summer Meeting: Volume 3: Fluid Machinery; Erosion, Slurry, Sedimentation; Experimental, Multiscale, and Numerical Methods for Multiphase Flows; Gas-Liquid, Gas-Solid, and Liquid-Solid Flows; Performance of Multiphase Flow Systems; Micro/Nano-Fluidics, The American Society of Mechanical Engineers , 2018, Vol. 3, article id T19A008Conference paper, Published paper (Refereed)
Abstract [en]
Industrial slurries transported in pressurized pipelines often consist of particles of broad size distribution. The broad particle size distribution affects slurry flow behavior in a pipe. A four-component model (4CM) predicts the frictional pressure drop in pipe flow of broadly graded slurry. The model considers Newtonian carrying liquid and splits the broadly graded solids into fractions (components) each of which contributes to the pressure drop through its own dominating friction mechanism expressed by a particular sub-model in the 4CM. The sorting of the solids into the components (carrier, pseudo-homogeneous, heterogeneous, fully-stratified) must be based on appropriate criteria. For the sake of simplicity, the 4CM currently uses threshold sizes of particles to split the solids into 4 components.
The goal of the present work is to analyze the existing criteria for the threshold between the pseudo-homogeneous component and heterogeneous component and for the threshold between the heterogeneous component and fully-stratified component. The analysis is based on a description of mechanisms governing particle support (suspension, deposition) of each particular solids component in slurry flow. It shows that the existing grain-size thresholds actually express certain proportions among threshold velocities of flow delimiting different slurry flow regimes. Such threshold velocities are the deposition-limit velocity, the initial-suspension velocity, and the full-suspension velocity. We discuss the proportions and demonstrate how properties (of liquid, solids, flow) and associated parameters additional to the grain size may influence the thresholds.
The analytical results are supported by experimental results for flow of individual components in a laboratory loop.
Place, publisher, year, edition, pages
The American Society of Mechanical Engineers , 2018. Vol. 3, article id T19A008
National Category
Water Engineering
Research subject
Water Resources Engineering
Identifiers
URN: urn:nbn:se:ltu:diva-72332DOI: 10.1115/FEDSM2018-83455Scopus ID: 2-s2.0-85056162769ISBN: 978-0-7918-5157-9 (electronic)OAI: oai:DiVA.org:ltu-72332DiVA, id: diva2:1276380
Conference
ASME 2018 5th Joint US-European Fluids Engineering Division Summer Meeting, Montreal, Quebec, Canada, July 15–20, 2018
2019-01-082019-01-082019-01-08Bibliographically approved