الفهرس 
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Abstract
The present investigations were performed to analyse the effect of various possible arrangements of the multiple functions hydraulic structure components on the inland navigation conditions downstream the hydraulic structures. Consideration was directed to establish safe inland navigation with particular emphasise to morphological and hydrological characteristics of the Nile River existing conditions and corresponding to ship design parameters. Employing the “SMS” 2-D depth averaged mathematical model, two main investigations were numerically carried out as the ideal reach and applied studies. The ideal study comprised three tests which were carried out on 6.0 km long straight stream representing main River Nile hydraulic and hydrologic characteristics. While the applied study was carried out on the existing River Nile bed configurations and hydraulic characteristics upstream and downstream the existing Assiut Barrages.A preliminary investigation was firstly carried out on the main River Nile reaches from downstream of Old Aswan Dam till the downstream end of Damietta and Rosetta branches .to demonstrate the existing river conditions in such a way as to design the ideal representative study reach. The corresponding morphological and hydrological conditions and main characteristics of the selected river reach during various possible flow discharges were performed. Applying the most up-to-date design specifications and techniques, different multiple functions hydraulic structure components - such as the gated sluiceway, hyDROPower plant, closure dam, and navigation lock chamber were elementarily designed. The design procedure was principally guided in such a way as to be acquainted with River Nile conditions and the newly constructed hydraulic structures at Isna and Naga-Hammadi as well as that at Assiut. To guarantee safe operation functions for the gated sluiceway; ensure maximum efficient hyDROPower generation; and fulfil safe navigation, the entire bed profile for the modelled reach corresponding to each test arrangement was achieved. The essential modifications in bed and slopes at the entrance and exits of the three components were worked out to form a full plan view for the site bed levels upstream and downstream the ideal study reach.Therefore, the “SMS” 2-D mathematical model was applied to produce the depth averaged flow pattern upstream and downstream the tested hydraulic structure corresponding to each tested case which reflects the possibility for strong variations in river morphology at the flow eddies and cross current zones. Also, the induced hydrodynamic depth averaged transverse velocity components downstream the tested hydraulic structure components corresponding to different flow conditions were examined in view point of safe inland navigation.XV The conducted three testing programs during the ideal reach studies comprised 79 tests which revealed the following results and achievements:1.The first program was mathematically carried out on such virtual representative straight river reach of 6.0 km length and constant top width to cover all possible factors that govern the current investigation. The study was carried out with dominant, maximum present and future flow discharges of 137, 233, and 350 millions m3/day respectively. The upstream and downstream water surface levels corresponding to each tested flow discharges were previously worked out. A total number of 36 testing alternatives which comprised three flow discharge cases, two possible flow distributions between the sluiceway and the hyDROPower plant, and 6 possible arrangements for the multiple functions hydraulic structure elements were tested applying SMS 2-D mathematical model. Four additional tests were carried out with the minimum navigable flow discharge to assess the resulted depth averaged transverse velocity component effects with respect to that of the dominant, and maximum present and future flow discharge results. The attainable results revealed that the most efficient and optimum hydraulic structure components arrangement in view point of safe inland navigation were assessed when the navigation lock was attached to the eastern river side and followed from the west side by either of the hyDROPower plant and gated sluiceway; then the closure dam till the western river side. The maximum inflow transverse velocity components during the two mentioned tests of (BA) and (BE) arrangements reached 0.527 and 0.711 m/s respectively which are more than the allowable safe limit values of 0.3 m/s. While the maximum acquired values corresponding to other components arrangements were generally much higher.2.The second program was carried out to examine the effect of river bed variations due to main morphological changes. The test was limited to the two components arrangements (BA) and (BE) of the same straight river reach and bed profiles that demonstrate different aspects of river morphology and bed configurations to justify the achieved results from the previous testing program. The testing program comprised three flow discharges with two possible flow distributions between the sluiceway and the hyDROPower plant; two possible arrangements for the hydraulic structure elements, and two cross section profile shapes which ultimately produce a total number of 24 study alternatives. The attainable results revealed that the hydraulic structure components arrangement (BA) where the hyDROPower plant is installed on the west side of the lock chambers can be considered as the most efficient arrangement in view point of the safe inland navigation. In this case, the corresponding maximum depth averaged transverse velocity component of 0.527 m/s was adopted as the most critical magnitude. Moreover, comparison of the attainable results from the two testing programs, revealed immaterial variations. For this reason, the adopted components arrangement of (BA) was assigned to establish the design method for guide wall length and inclination which can be erected downstream the lock chamber to reduce the acting hydrodynamic transverse velocity to the allowable safe limit.XVI 3.Considering that 0.3 m/s is the maximum permissible magnitude for the depth averaged transverse velocity component in view point of the inland navigation condition downstream the hydraulic structure, the third testing program was carried out to establish such design method for guide wall length. The adopted testing program comprised 15 alternative configurations of 5 guide wall lengths and 3 inclination angles, by using “SMS” 2-D mathematical model with components arrangement (BA). To assess the best fitting mathematical expression for the attainable scatter data, three relationships between the resulted hydrodynamic depth averaged transverse velocity component and the guide wall length for different inclination angles were developed. Those revealed that to guarantee an appropriate transverse velocity component of less than 0.3 m/s, a guide wall length of 108.0 m; 91.8 m; and 80.6 m at the case of using guide wall inclination of 0.0; 5.0; and 10.0 degrees respectively could be applied.The applied study was then carried out to examine the attainable results from the conducted three tests during the ideal river reach investigations.The existing river bed levels and morphological conditions upstream and downstream the newly designed and tested multiple functions hydraulic structures at Assiut were utilized. Tests were firstly carried out to calibrate the ”SMS” 2-D mathematical model according to the conducted field measurements downstream the old Assiut barrages in September 2009 to simulate the existing river flow morphological conditions. As the calibration results were in good agreement with the field measurements, the historical records for the existing barrages were utilized to distinguish the actual hydrological flow conditions corresponding to the dominant, maximum present and future discharges of 97.11, 184.00 and 350.00 millions m3/day respectively. A testing program comprises three flow discharges, two discharge distributions through the sluiceway and hyDROPower plant, and two hydraulic structure elements arrangements which ultimately produce a total number of 12 tests were carried out. Distribution of the induced depth averaged transverse velocity component along 500 m distance downstream the wing wall of the double navigation lock chamber was performed for each test. The attainable results revealed that arrangement (Rec) which is the recommended where the hyDROPower plant is directly installed on the west side of the double navigation lock chambers is the most efficient arrangement in view point of safe inland navigation. The percentage reduction in the effecting transverse velocity component in this case reaches 22.2%, 27.6%, and 22.4% for the case of the maximum, minimum, and average values respectively comparable to that of the (Con) constructed arrangement which assured the attainable results from the ideal revel reach testing results.Therefore, analysis of the attainable results from the two ideal and applied studies revealed that the most efficient and optimum multiple functions hydraulic structure elements arrangement in view point of providing safe inland navigation downstream the hydraulic structure and river morphology would be arrangement (BA). In this case the navigation lock chamber was directly attached to the river side and followed by the hyDROPower plant; gated sluiceway; then the closure dam. This - in other words means that the induced hydrodynamic transverse velocity components perpendicular to the navigation XVII XVIII units would be tremendously reduced and minimized downstream the hydraulic structure when applying the recommended elements arrangement through the ideal river reach testing programs. Moreover, the developed design method for guide wall length and inclination downstream the navigation lock chamber could be effortlessly applied to guarantee an appropriate transverse velocity component of less than the permissible value.