Tesis doctoral de Albert Herrero Casas
Fluvial bifurcations are systems that have a great influence on human society. Their formation and evolution can affect to activities as agriculture or industry and a good knowledge of the mechanisms that affect the processes involved can be determinant for a proper land management. From a geometrical point of view, diversions or lateral intakes are a particular case of fluvial bifurcations in which one of the downstream branches exits laterally while the other follows the same direction as the incoming channel. Diversions are characterized by a significant trend of sediment to deviate towards the lateral branch. the first part of this document describes the experimental work performed in the fluvial morphodynamic laboratory in barcelonatech university. Water and solid discharge distributions, as well as bed and water surface levels are measured along the model, during tests with different total water discharges. Results confirm the sediment distributions reported in the literature and but also highlight the influence of bed bathymetry evolution and three-dimensional flow patterns in the local sediment transport of the diversion area. A threshold value is found for total discharge, above which a vortex is formed in front of the diversion entrance and a scour hole is formed in the first stretch of the main channel downstream of the diversion. an energy balance equation is proposed between upstream and downstream of the diversion taking into account the energy losses associated with the vortex, and a good comparison is found when tested against the experimental results. A nodal equation that relates water discharge to sediment discharge distribution is developed considering separately bed load and suspended sediment transport. Calculated values of sediment discharge ratio compare reasonably well with experimental values. Joining these equations, uniform flow, transport capacity and mass continuity equations for water and sediment, a theoretical model is proposed to evaluate the equilibrium situation of a fluvial diversion in terms of water discharge, sediment discharge, water depth and bed slope in both downstream branches.
Datos académicos de la tesis doctoral «Experimental and theoretical analysis of flow and sediment transport in 90-degree fluvial diversions.«
- Título de la tesis: Experimental and theoretical analysis of flow and sediment transport in 90-degree fluvial diversions.
- Autor: Albert Herrero Casas
- Universidad: Politécnica de catalunya
- Fecha de lectura de la tesis: 07/06/2013
Dirección y tribunal
- Director de la tesis
- Allen Bateman Pinzon
- Tribunal
- Presidente del tribunal: gary Parker
- Alberto Falqués serra (vocal)
- enrique Peña gonzález (vocal)
- michele Bolla pittaluga (vocal)