Flow Under Tilt Surface for High‐Rate Settling
Publication: Journal of Environmental Engineering
Volume 111, Issue 3
Abstract
A clear layer flow rising under inclined surfaces (particle‐free flow stratified on the suspension), which can be utilized for particle settling enhancement, has been theoretically analyzed in order to apply it to design and operation of high‐rate settlers in water and wastewater treatments. The flow proves to be driven by settling convection due to the density difference between the clear liquid and the suspension. A mathematical model for the flow simulation has been obtained by making use of the boundary layer approximation and the clear‐layer‐averaged inertia terms in the momentum equations. A dimensionless number, Γ, which controls the model and is given by the ratio of Grashof number, Gr, to Reynolds number, R, plays an important role in the flow. The flow velocity and the layer thickness predicted by the analytical solutions agree fairly well with previous experimental results observed in a batch settler to verify the analysis.
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Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 111 • Issue 3 • June 1985
Pages: 285 - 303
Copyright
Copyright © 1985 ASCE.
History
Published online: Jun 1, 1985
Published in print: Jun 1985
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