الفهرس | Only 14 pages are availabe for public view |
Abstract basin is a short length of unexposed channel placed at the foot of a spillway or any other hydraulic structure of the supercritical flow. The stilling basins may have large sizes, which cost millions of Egyptian Pounds and effort. For example, New Esna Barrage, New Naga-Hammadi Barrage, New Assiut Barrage, and other barrages on the Nile River and its branches. Therefore, if a stilling basin placed at a specific location from the structure and limited size (length and width) can be properly designed, it saves cost, time, and effort. The main objectives of this study are to investigate the effect of different locations and dimensions of stilling basin pools from regulator gates and study its effects on the characteristics of the submerged hydraulic jump, velocity profiles along the basin, and local scour downstream stilling basin. Experiments were conducted employing a wide range of Froude numbers, different tailwater depths, and different stilling basin locations and dimensions. The main output of this research is determining the best location for the stilling basin pools from the structure gates that correspond with the maximum energy dissipation, minimizing the stilling basin size, and minimizing the length and high of the hydraulic jump for fewer scour problems. These investigations are carried out by using physical modeling. The physical modeling study is conducted using a flume with dimensions of 1.0 m wide, 26.0 m long, and 1.20 m deep. The flume sidewalls along the entire length are made glass with steel frames to allow visual inspection of the flow patterns and stability of bed material. Different discharges and water depths are used to determine the best location and dimension of the stilling basin pool. The study indicated that design (C) with stilling basin at a distance of 40 cm from the sluice gate, the length of the basin is 60 cm, and the depth is 15 cm is the best design that gives maximum energy dissipation and minimum scour depth. |