Sediment Transport and Dunes in Pipe Flow
نویسندگان
چکیده
We propose a two-phase model having a Newtonian rheology for the fluid phase and friction for the particle phase to describe bed-load transport in laminar pipe flows. This model is able to provide a description of the flow of the mobile granular layer. When the flow is not significantly perturbed, simple analytical results of the particle flux varying cubically with the Shields number can be obtained. This prediction compares favorably with experimental observations of the time-evolution of the bed height in conditions of laminar flow. A simple linear stability analysis based on this particle flux also accounts reasonably well for the dune formation observed.
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