Calculation of Optimum Dimensions and Array of Submerged Vanes at Intakes Using the Feasible Direction Method

In recent years, installation of plates in canal beds have been considered for sedimentation control and bed load reduction at canal intake. These planes, called submerged vanes, are different in dimensions. They are installed at intakes in-group with reasonable distance from each other. Presence of these vanes at intakes initiate transverse shear stress on river bed and causes sediment transport in the transverse direction. Investigation of flow and sediment transport equations, along with different experiments on physical models, have resulted in a suitable range of sizes and distances for vane installation. But, the determination of optimum sizes and distances for vane installation so as to minimize sedimentation requires the use of optimization techniques.

In this study, the hydrodynamic and optimization models of the vane system are first introduced. As the flow and sediment transport governing equations at intakes was nonlinear, the feasible direction method is used. Optimum size of vanes, distances between them at longitudinal and transverse directions, and the angle of flow inclination have also been determined. The optimum quantities of vane parameters were used to calculate the river bed profile at intakes by Wang et. al. [1] procedure. Comparison of the obtained results with Wang el. al. [1] recommendations confirms the advantage of vanes instalation at optimum conditions to control sedimentation.

Keywords: Submerged Vanes, Feasible Direction, Intake and Sedimentation