Collisional transport model for intense bed load

Title:

Collisional transport model for intense bed load

Creator:

Matoušek, Václav and Zrostlík, Štěpán

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:9f3e26ee-e4e5-434b-adb3-9ee9de9d5204
uuid:9f3e26ee-e4e5-434b-adb3-9ee9de9d5204
doi:10.2478/johh-2019-0027

Subject:

granular flow, sheet flow, sediment transport, grain collision, tilting flume experiment, and kinetic theory

Type:

model:article and TEXT

Format:

počítač and online zdroj

Description:

In an open channel with a mobile bed, intense transport of bed load is associated with high-concentrated sediment-laden flow over a plane surface of the eroded bed due to high bed shear. Typically, the flow exhibits a layered internal structure in which virtually all sediment grains are transported through a collisional layer above the bed. Our investigation focuses on steady uniform turbulent open-channel flow with a developed collisional transport layer and combines modelling and experiment to relate integral quantities, as the discharge of solids, discharge of mixture, and flow depth with the longitudinal slope of the bed and the internal structure of the flow above the bed. A transport model is presented which considers flow with the internal structure described by linear vertical distributions of granular velocity and concentration across the collisional layer. The model employs constitutive relations based on the classical kinetic theory of granular flows selected by our previous experimental testing as appropriate for the flow and transport conditions under consideration. For given slope and depth of the flow, the model predicts the total discharge and the discharge of sediment. The model also predicts the layered structure of the flow, giving the thickness of the dense layer, collisional layer, and water layer. Model predictions are compared with results of intense bed-load experiment carried out for lightweight sediment in our laboratory tilting flume.

Language:

Slovak

Rights:

http://creativecommons.org/publicdomain/mark/1.0/
policy:public

Coverage:

60-69

Source:

Journal of hydrology and hydromechanics | 2020 Volume:68 | Number:1

Harvested from:

CDK

Metadata only:

false