Author(s): Anirban Mandal; Z. Ahmad

Linked Author(s):

Keywords: bevel angle; submerged vane; angle of attack; leading edge; local scour; scour volume reduction

Abstract: Submerged vanes refer to aero-foils that are typically positioned at a specific angle to the flow direction for sediment management in rivers. One of the main issues linked to the application of submerged vanes is their structural disintegration caused by local scour near their tips. The efficiency and performance of a submerged vane on sediment management and scour control highly depend upon the shape and dimensions of the vane. The present study is on local scour at the leading edge of the vanes for their different bevel angles. A series of experiments were conducted in a straight rectangular flume under clear- water conditions using five different vane shapes, which include a standard rectangular vane and four vanes with leading- edge cuts at bevel angles of 30, 45, 60, and 70 degrees relative to the base. Experimental studies demonstrated that the scour hole was shifted from the leading edge to the downstream of the vane due to the increasing bevel angle. The results showed that the bevel-submerged vane outperforms the rectangular vane by reducing the local scour volume at the leading edge 44.5, 56.65, 93.54, and 100 percent for bevel angles of 30, 45, 60, and 70 degrees, respectively. So, cutting the leading edge with an angle is highly efficient for controlling the local scour around the vane.

DOI: https://doi.org/10.3929/ethz-b-000675921

Year: 2024