Numerical Investigating Effect of Obstacle's Upstream Angle and Water Depth of Reservoir on Controlling Turbidity Current

In addition to decrease in useful lifetime of dams, the entrance of turbidity currents into reservoirs and their sedimentation near dam walls result in reduction of the useful volumof dam’s reservoirs, blockage of irrigation valves, and damages to the power plants. As a result, a large number of dams have been abandoned because of reservoirs sedimentation. One method thatcan control the turbidity current in to reservoirs is construction of obstacle. Using an obstacle can lead to the deviation or dissipation of the turbidity currents in reservoirs. In this paper, the effects of upstream angle of the obstacle as well as the water depth of reservoirs on controlling turbidity currents, were studied. For this means the Finite element method was employed using ANSYSY-CFX software. The results indicated that for subcritical and supercritical turbidity currents, as the level of water in reservoirs was declined, the efficiency of using an obstacle in controlling turbidity currents was decreased. Furthermore, when the upstream angle of the obstacle was increased, the obstacle was more capable of controlling the turbidity current.