Enhancing baffle columns’ performance to mitigate sedimentation at intake structures

Abstract

The improvement and capacity increasing of hydropower stations have brought attention to the intake structures of water-cooling systems, which suction water from alluvial channels. The accumulation of sediment in the vicinity of these intake structures poses significant operational challenges, such as strong vortices, and irregular flow distribution at pump intakes. One effective approach is the implementation of a sediment deflector system using baffle columns as avoided wall (L-Shape profile) with specific dimensions and arrangement to allow water to go through while preventing sediment ingress into the power station intakes. L-Shape profile means double voided walls, one of them parallel to flow direction while the other wall perpendicular to the flow direction in the upstream of the intake structure. The objective of this study is to optimize the performance of the baffle columns of the deflector system in mitigating sedimentation in front of the intake structures. To achieve this, an undistorted physical model with scale 1:50 is utilized to analyze the impact of a defined angle between the two voided walls of the deflector system. Three trials by changing the angle of the double voided walls (L-Shape profile) from 90° to 120°,135°, and 150°. The results of this study indicate that as the inclination angle of the deflector system increased to 150°, it resulted in uniform flow efficiency in the direction of the flow, less accumulative sedimentation ingress the intake.