Hydraulic Experiment on Flushing of Accumulated Sand under Movable Gates of Diversion Dams

Abstract

The processes of the gate flushing accumulated sand under the movable gates of the diversion dam were investigated through several hydraulic experiments. The experiments took into account the effect of quantity of flow, the water difference in the upstream and downstream, and the distribution of sand as dominant factors. The experimental results show: 1) flushing is performed regardless of any other factors when the quantity of flow is large. 2) Sand accumulates downstream in a shape similar to a mountain when the downstream water level is high, and that this influences the processes of flushing. 3) In the case of a one-sided distribution of sand, flushing becomes difficult because most of the flow quantity passes by the section without sand. 4) The accumulated sand is flushed within a narrow area around the gate.