Experimental Study of the Use of Submerged Vanes in Protecting the External Bank of the River

One of the most important issues in river engineering science is the river training in the bend of the rivers. Training operations are carried out to prevent changing the curvature in the bend of the rivers, protecting the external bank against erosion, and also controlling sedimentation in vicinity of the internal bank of the rivers. The use of submerged vanes is one of the practical methods used to train the rivers, stabilize the bank of the rivers and protect it against erosion. Submerged vanes are guidance stream structures that are installed at the river bed with an angle to the main flow and designed to adjacent flow pattern improvement. In this study, after dimensional analyzing and determining the effective dimensionless parameters, submerged vanes are placed in three lengths and three different angles in a channel with a mild sinuosity curvature and their performance was compared with each other. The results showed that by increasing the length and distance between submerged vanes in a constant Froude number, the maximum scour depths, increases, so that the maximum scour depth was observed for first vane in the angle of 110 degree and length of 2.66 H0. The most suitable and destructive angles for the establishment of submerged vanes are equal to 140 degree and 110 degree, respectively.