Investigating the Effect of Convergence and Submerged Vanes Composition on the Hydraulic of the Lateral Intakes’ Inlet Flow at 90º River Bends

In this study, experiments are carried out to determine the deviation flow into the intake in a 90º convergent bend, aiming to investigate the effect of flow characteristics on deviation flow with and without submerged vanes. The effective variables include Froude number, convergence, and submerged vanes’ angle. For this research, a Rectangular channel with a 90º arc was used, which was studied using four different discharges, four different angles of submerged vanes and four degrees of convergence of the end of the channel. According to the results, the deviation flow to the intake increases by converging the laboratory flume. As the end of the flume is converged, the deviation flow is further increased. As the flume is converged (b/B) from 0 to 0.75, the deviation flow is increased from 64.9 to 81.4%, showing a 16.5% increase. Deviation flow is decreased by installing submerged vanes. A decrease in submerged vanes’ angle reduces the deviation flow. Compared to the model without a submerged vane, deviation flow is decreased by 14.9, 9.9, 6.8, and 2.3% by installing submerged vanes at angles of 25, 30, 45 and 60º, respectively. Deviation flow is also decreased by increasing the Froude number, such that it decreases by 5.3% with the increase of Froude number from 0.14 to 0.23.