TY - JOUR ID - 8557 TI - Introducing a New Dam-Type Sediment Excluder Method at Dam Reservoirs for Sediment Mitigation JO - Journal of Hydraulics JA - JHYD LA - en SN - 2345-4237 AU - Pishgar, Reza AU - Keshavarzian, Alireza AD - MSc. Graduate of Water Structures Engineering, Water Engineering Department, Shiraz University, Shiraz, Iran AD - Professor of Water Engineering, Department, Shiraz University, Shiraz, Iran Y1 - 2014 PY - 2014 VL - 9 IS - 2 SP - 53 EP - 67 KW - Efficiency KW - Extraction KW - Reservoir Sedimentation KW - Suspended Sediment DO - 10.30482/jhyd.2014.8557 N2 - In this paper a new method for mitigation of dam reservoirs sedimentation is introduced and its performance is evaluated. This method includes a self-cleaning and permanent function structure resembling a short dam built across the rivers discharging into the dam reservoir. This structure, called Dam-Type Sediment Excluder (DTSE), extracts suspended sediment from flows upstream of reservoir through a middle opening (gate) and prevents entrance of sediments into the reservoir. In this study, using laboratory experiments, the efficiency of the proposed DTSE method was examined under three ratios input discharges, three middle opening relative heights and the output (bypass) to input flow rates of 0.1, 0.2 and 0.3. The results showed that: 1) the efficiency of the DTSE increased with increase of middle opening height, 2) increase of bypass flow ratio affects the model efficiency and sediment concentration of bypass flow in a positive and negative manner, respectively. Therefore, between three flow ratios, bypass flow ratio of 0.2 is the optimum one, due to the water loss of 20% and proper efficiency, 3) the maximum extraction efficiency of the model was found to be about 40% while the average optimal efficiency, for bypass flow ratio of 0.2, was about 26%. Therefore, the new DTSE method could be introduced as an effective method for sediment mitigation, in comparison to other reservoirs sedimentation mitigation methods such as density current venting with only 20% efficiency. UR - https://jhyd.iha.ir/article_8557.html L1 - https://jhyd.iha.ir/article_8557_3b7dd6dd1d4b35cc45dae3f5ecb9a1cf.pdf ER -