الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Spillway associated with flip bucket structure is considered as an effective evacuation tool in dam structural components. Huge destructive flood can be dissipated safely through this structure. Poor geometrical, structural and hydraulic design of this structure may cause serious damage followed by failure in the dam’s stability.
The main aim of the study was orientated to introduce practical proposed modifications to avoid the critical damage zones in a real ogee spillway flip bucket structure. Proposed solutions were calibrated and assessed based on the numerical simulation process using computational fluid dynamics (CFD). Optimum modification was classified according to its high ability in dissipating the dangerous flood energy away from the dam’s body. Disposed hyper flood was carried to safe qualified location to ensure the downstream stability.
This main aim was preceded by an initial another aim of assessing the most reliable turbulent model in simulating this multiphase flow type. Four different turbulent models were examined such as: standard k-epsilon model (SKE), realizable k-epsilon model, renormalization group model (RNG) and detached eddy simulation model (DES). The multiphase water-air flow process was simulated using volume of fluid (VOF) method. The ANSYS FLUENT software was used in simulation analysis.
Results of each turbulent model were compared with results of physical (or experimental) model. Several physical models were investigated for ogee spillway and flip bucket individually and in other combined case. Multiple
comparing criteria of flow profiles, velocity values, and pressure values were examined. Detached eddy simulation (DES) process achieves the most reliable results for all cases.
Subsequently, DES was used for the main analysis of the damage simulation analysis and its modifications. Several constraint modifications of path curvature and its inclination angle were examined. Successful geometrical adjustment was developed for solving the damage problem.