الفهرس 
CHAPTER 1 INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In the present time, the Ministry of Water Resources and Irrigation (MWRI) starts to construct new barrages across the River Nile and the main canals to replace the oldest ones, which are not able to withstand the requirements of increasing head difference between the upstream and downstream water levels upon the gates.
This research is focused on investigating experimentally the flow characteristics downstream the vertical sluice gates of Bahr Yousef regulator in case of flow over gate and flow under gate and the proper design for stilling basin with high efficiency in dissipation of water energy downstream the vertical gate with low cost.
In the present study experimental work was carried out on a 2-D flume with 1.0 m wide, 26.0 m long and 1.2 m deep, with discharges range from 22 to 395 l/s at the Hydraulics Research Institute, (HRI). There were three phases; one (flow over the gate), phase two (flow under gate) and phase three (fully open gate). Both phase one and phase two have four cases, phase three was studied to check the efficiency of the structure.
In Case1 and Case 2 the discharge flow through the total no of gates (four gates), the discharges ranging from 18.52 m3/s to 227 m3/s (Proto Type) that corresponding to 22 L/S to 269 L/s in the model. The rip-rap protection covered distance 71.4 m upstream stilling basin and covered distance 41.74 m from the end of 30 m concrete blocks area downstream new regulator in Case 1. In Case2 Riprap protection covered distance 71.4 m upstream stilling and covered distance 71.74 m from the end of basin area (Apron) downstream new regulator. The D50 of the Riprap that covered the downstream area is 40 cm. In Case 3 and Case 4 the discharge flow through only three gates, the discharges ranging from 18.52 m3/s to 227 m3/s (Proto Type) that corresponding to 29 L/S to 359 L/s in the model. The rip-rap protection covered distance 71.4 m upstream stilling and covered distance 71.74 m from the end of basin area downstream new regulator. The D50 of the Riprap that covered the downstream area is 40 cm in Case 3. The D50 of the Riprap that covered the downstream area is 20 cm in Case 4.
Fifty-four experimental tests were carried out. The experimental tests involved the observations and measurements of hydraulic phenomena in one single bay of the regulator in case of flow under/over gate. In these tests, there was a group of variables such as; the gate opening, flow rate, number of gates opening, and D50 of riprap protection. The influence of these parameters on the length of stilling basin and rip-rap size was investigated downstream the vertical gates. The measurements were taken at six profiles A, B.C, D, E and F in different four cases. Profiles from A to F located repressively at 11.72m; 20.48m; 28.98m; 43m; 58.05m and 73.09m downstream the gate. Comparative analysis between flow under the gate and flow over the gate was carried out.
The results showed that the case of flow under gate gave more normal velocity distribution with low turbulent and high efficiency in dissipation of water energy downstream the vertical gates, and it was recommended for the operation of the regulator. The best design was (The design of Case 4) as it was safe design in case of operation four gates or three gates (one closed vent); moreover, it was more economic when we replace 30m of concrete blocks by riprap layer with d50 =20 cm as it minimized the cost of the protection layer by 80 %.