Trapez Kanallarda Savak Kapağı ve Savaklarla Enerji Azaltımının Deneysel ve Sayısal Analizi

Abstract

In open channels, only one of the sluice gates or weirs is often used for regulation purposes to limit the acceleration of flow through the channel and to help reduce the forces around the water structures. When the sluice gates are used single, depending on the tail water depth and the gate opening, all cases might experience free or submerged flow conditions and hydraulic jump might occur at the downstream. In this case, it is possible to damage the submerged or semi-submerged structures in this area due to the high flow velocity and high hydraulic energy at the downstream of the gate. The combination of weirs and gates can be preferred both to preserve the stability of the river bottom and to prevent damage to structures such as submerged pipes and transmission lines stretching across cross-sectional direction. In this study, the variation of the flow characteristics in the channel and around the pipeline extending across the channel cross-section was investigated when varying cross-sections weirs with the sluice gate are used together. Experimental flow velocity and water levels are measured for different discharges. These measurements were used to determine the boundary conditions of the computational fluid dynamics (CFD) software and to verify the flow property values obtained by CFD. After the verification, the velocity, pressure and specific hydraulic head values of the points that could not be measured experimentally with CFD software were also obtained. As a result of both experimental and numerical analysis, it has been seen that hydraulic head can be reduced significantly by using the gate and weir structures together. The effect of weir geometry on energy loss is clearly seen at high discharges. By using the two structures together, both the water depth in open channels will be kept at the desired level and possible damage due to water forces acting on underwater structures will be prevented.