Study of the Effect of the Angle of Submerged Vanes on Sediment Control in Lateral Intake at a 180 Degree River Arc

One of the methods for sediment control in lateral intake can be application of submerged vanes in front of the inlet. The establishment of submerged vanes in flow path causes a flow diversion toward the inner arc. In this research, the performance of submerged vanes on sediment transport to the inlet at 180 degree of intake has been investigated. Several experiments were carried out in a laboratory channel made of Plexiglas at a 180-degree arc, under clear water condition. In this research a series of experiments were done by inserting several vanes made of Plexiglas in front of lateral intake. Experiments were done by using two rows of parallel vanes with variable angles at four different discharges under two conditions of with and without vanes. In each experiment, the main channel discharge and diversion channel discharge, sediment discharge through the diversion and transmission were measured. The results of research showed that the performance of the parallel submerged vanes in diverting the path of sediments depends on contacted vanes angle by water flow. Also, entering water rate is directly proportional with entering sediment rate and entering sediment rate are increased with the increase of entering water rate at all angles. Suitable performance in reducing the sediment transport to the inlet was observed at an angle of 15 degrees of vanes relative to the axis of water flow. In other words, by increasing the angle relative to the axis of flow, sediment transport to the inlet will be increased.