The effect of the sill heights at the end of the stilling basins to the scour

Energy of the water which is leaved from the spillway of the dams which have high head, is quite big. The river bed which is near the downstream of the dams, is scoured with the effect of this water which is leaved from the spillway, has big energy. For the security of the dams and near buildings, the scour must be controlled with the energy dissipation of the water. To dissipate this energy, a sill is built at the end of the stilling basins of the dams. Height of these sills effect the depth and place of the scour.In this study, the sill heights which we need to get lower of the scour to the least, was researched. This study includes seven sections. In the first section; introduction was presented. In this section, especially, the aim of this study was given. In the second section; summary of literature was presented. In the third section; scouring with water jets was told. In the fourth section; informations about sills were given. In the fifth section; the samples about the scours at the end of the stilling basins were given. In the sixth section; exprimental setup and the making of experiments were told. The results about graphics were explained and discussed by drawings. In the seventh section; the results were given. According to the results of the experiments that were made in this study, increasing the height of the sill decreases the scouring. Also increasing the flow increases the scouring, increasing the water height of the end of stilling basins decreases the scouring.