Control of Sediment Entry into Intake Canals Using Submerged Vanes with Collar

Abstract

Intake canals transport water and sediments from main rivers to power plants, irrigation fields, and for various other purposes. Increased sediment load in the intake canal leads to reduction in the quality and quantity of water. Submerged vanes are installed at the entrance of intake canals to counteract the secondary circulation and reduce the sediment entry into the intake canals. In the present study, collars have been introduced to submerged vanes to test its performance in the reduction of both sediment entry and local scour around vanes. The vane angles tested are 15°, 35°, 40° and 45°. The ratio of vane spacing to vane height is 5 and the two collar diameters considered are three and four times the vane height, respectively. It is found that 40° is the optimum vane angle for maximum reduction in sediment entry into the intake canal of 85.36%. Collars reduced the local scour and sediment entry (%) by a maximum of 69.08% and 24.84%, respectively, for a 15° vane angle. However, introduction of collar reduced the performance for vane angles 35°, 40°, and 45° in controlling sediment entry into the intake canal.