An efficient self-cleaning dam-type sediment excluder upstream of the dam reservoir

Sedimentation is almost a serious problem for reservoir dams due to loss of storage, malfunction of bottom intakes, corrosion, and damage to power generators, increased flood risk, water quality degradation, and other environmental degradation problems. There are some methods of sediment removal from the reservoir, such as dredging and flushing. The above techniques are not feasible for all reservoirs due to high cost and low efficiency. In this paper, a new sediment extractor referred hereafter as Dam-Type Sediment Excluder (DTSE) is introduced. The self-cleaning DTSE excludes suspended sediment from the river flow upstream of the reservoir and then bypasses the river downstream of the reservoir. The efficiency of the proposed DTSE was examined under different excluding flow rates, opening heights, inlet flow Froude numbers, and sediment concentrations. This research also investigates the influence of suspended- sediment concentration profile on the model efficiency. The results indicate that the efficiency of the DTSE is highly sensitive to the flow velocity and the middle intake location and height. The maximum extracted efficiency of the model was found to be about 40%, while the average optimal efficiency was 26%.