Modelling of simple prismatic channels with varying roughness using the SKM and a study of flows in smooth non-prismatic channels with skewed floodplains

[摘要] Accurate modelling, both numerical and physical, is vital to further our understanding of flow in rivers. This thesis examines both methods of flow applied to two distinct problems; numerical modelling of flow in simple channels with heterogeneous roughness and physical modelling of flow in compound channels with skewed floodplains. In this thesis, the Shiono and Knight Method (SKM) is applied to homogeneously and heterogeneously roughened channels. The SKM is shown to be capable of accurately predicting the lateral distributions of depth-averaged velocity and boundary shear stress for both roughness types. Furthermore, the percentage shear force on the wall of a channel is accurately obtained for both roughness types and guidance is given as to the choice of the three calibration coefficients the model requires, namely f, l and G representing friction, eddy viscosity and secondary flow respectively. Finally, physical modelling has been undertaken on compound channels with skewed floodplains in addition to a full review of the work undertaken at a larger scale in the Flood Channel Facility. As a result appropriate expressions for shear force and apparent shear forces acting on the horizontal and vertical interfaces have been established.

[发布机构] University:University of Birmingham;Department:School of Engineering, Department of Civil Engineering

[关键词] T Technology;TC Hydraulic engineering. Ocean engineering