Experimental investigation of SFM structure impact on sediment flushing efficiency of reservoirs outlet gates

sedimentation in reservoirs is a great problem, especially around the outlet gates during their operation. sediment flushing efficiency from outlet gates is very low too. in this paper a new method to increase the efficiency of sediment flushing is prepared. in this method a structure namely SFM (Sediment Flushing Motivator) consisting of two rows of piles installed inside the reservoir on upstream of gates is introduced. one to six pairs of piles with a permeability of 0%, 28.6%, 37.5%, 42.9%, 50% and 60% at two parallel rows at a distance of eight cm from each other were installed. uniform non-cohesive sand material with mean particle sizes of 0.67 mm was utilized as the bed packed sediments. the results show that at the best condition (permeability of 37.5% and row distance of eight cm) the mean flushed sediment volume increases by 161% compared to the reference test (the situation in which no SFM structure is utilized).