Author(s): Yasser A. Moussa, Mohamed A. Awad
Linked Author(s): Yasser Moussa
Keywords: Positive step, local scour, hydraulic structures, hydraulic jump
Abstract: Scour downstream of multi-vents regulator represents a great harmful effect to the stability of such hydraulic structures. In this paper, the scour formed downstream of stilling basin is investigated experimentally for different positions of positive step. The experimental work is carried out in a 0. 4m wide and 44. 1m long rectangular channel. The experimental measurements include contours of scour depth, location of maximum scour depth and velocity vectors along rigid and mobile bed. The location of positive step close to vertical gates (Lo= 44%) decreases the scour depth and length by 72% and 65%, respectively. In addition, as the positive step moves away the vertical gates, asymmetric flow is formed and large dimensions of scour holes are generated downstream of stilling basin. Multiple linear regressions are used to have empirical correlations to predict maximum local scour depth and length downstream multi-vents regulator with correlation coefficients of 82% and 86%, respectively. The simulated results agree well with the measured data
Year: 2017