Review of Turbulent Shear Boundary Layer by Soil Slurry Transfer in Pipe

Abstract

In the classification of the slurry transportation processes, sediment has been mostly classified as suspended sediment flowing with fluid or sediment sank to the bottom of riverbed, though there have been few cases of clarifying the boundary of the two phenomena. A boundary layer is a major factor in determining the capability of transferring sediment. In case of discharges flowed into sewer pipes, most of them flow into as a mixture fluid and soil slurry based on the occurrence of rainfall, and show characteristics of turbulent flows. In this study, an analysis model capable of predicting soil slurry flows within actual sewer pipes based on a numerical analysis model, and proposed a method of estimating boundary layers in the sediment flow. To verify the analysis model, the volume fractions in the pipes were compared based on cases of similar studies. To review the process of transferring sediment, the velocity field and volume fraction by flow conditions including slurry inside of pipes was studied. Based on the result, criteria on the formation of a shear boundary layer were expressed as for figural style by using shear velocity rates and settling velocity rate of particles in pipes. Keywords: Slurry, Boundary Layer, Transportation, Numerical Analysis, Shear Velocity, Settling Velocity