Page - 194 - in Book of Full Papers - Symposium Hydro Engineering

efficiency, one can change the share of the sediments entering the orifice and the sediments settled on the basin floor compared to the no-vane mode. How these vanes work (sedimentation or settling from the floor) depends on their distance from the orifice. At a low radial distance (areas 1 and 2), they increase sedimentation on the floor by preventing the movement of sediments towards the orifice. But at a large radial distance (areas 3 and 4), they remove sediments from the floor by directing the floor sediments towards the flushing orifice so that increased sedimentation on the floor was observed for R2 and R2 3, and R2 3 4 arrangements and sediment removal was observed on the floor for R3 and R4 and R3 4 arrangements. Also, tests for inserting curvature submerge vanes in three modes of radial sections showed that the lower number of radial sections, the better the settling on the floor will be done. Among the three modes, S4 (90-degree radial sections) had higher sediment removal efficiency. 5 Acknowledgments The writers wish to sincerely thank Associate Professor mojtaba saneie for his suggestions during various stages of this study. Financial assistance received for this study from the Soil Conservation and Watershed Management Research Institute is gratefully acknowledged. Notation d50 = median diameter of sediment grains [mm] Hv = Height submerged vanes [cm] Lv = Length submerged vanes [cm] R = The areas in which vanes are placed [-] S = number of radial section in which vanes are placed [-] ƞT = Total settling efficiency [-] ƞo = Orifice settling efficiency [-] ƞB = Basin floor settling efficiency [-] WT = The total weight of sediments entered to the basin [kg] Wo = The weight of sediments entered to the flushing orifice [kg] WB = The weight of sediments at the floor of basin [kg] Gʹ = The efficiency of the sediment flushing at the floor [-] ƞ'B = The settling efficiency at the floor of the basin without curvature submerged vanes [-] References Athar, M. (2000). Study of vortex chamber type extractor. PhD thesis. Department of 194