Local scour profiles downstream of adverse stilling basins

Abstract

In this paper, scour profiles downstream of adverse stilling basins due to the submerged jet issuing from a sluice gate, were investigated. Experiments were conducted in a wide range of sediment sizes, incoming flow Froude numbers, tailwater depths, length and slope of stilling basin. The results showed that the scour profiles at any bed slope are similar in shape. However, the longitude evolution of scour profiles and the volume of eroded materials were increasing in accordance with slope of basin. It was observed that the maximum depth of scour hole occur at the vicinity of side walls and slightly decrease towards the centerline. A polynomial equation was derived to describe the nondimensional scour profiles at different slopes. Based on experimental data, the scour characteristics have been correlated with the time of equilibrium stage by developing some empirical relationships. Finally, a power-law equation was derived and fully defined to include the dimensions of scour hole time scale and geometry of sluice gate.