الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Lateral intake is a structure created next to a main channel to distract part of the flow from the channel. These intakes are used by hydraulic engineers to divert flow to irrigation systems and water supply schemes. 90-degree lateral diversions are the easiest way to divert the flow from main channels. With approaching of the flow to the intake, the flow accelerates in the transverse direction and divide in two parts. the
first is directed into the lateral intake and the second into the main channel. The overall flow pattern in the lateral intakes is fully three-dimensional. That is why many
laboratories, theoretical and numerical studies were performed on the flow pattern of such hydraulic structures. Intake is an open channel that usually has a non-uniform flow along its length. Velocity and direction change in the lateral intake lead to nonuniformity of the flow, sediment transport, whirlpools and/or swirls, which consequently decrease intake abstraction efficiency. High maintenance cost is regularly paid in order to dredge the sedimentation areas and to guarantee and maintain abstraction efficiency. Sediment movements usually cause corrosion to the turbine blades, which consequently will increase maintenance cost too. River flows at main channels and diversions are geometrically similar and belong to the same class of gravity-driven flows that divided into two directions and two flow ratios. Therefore, related to all these points and problems, the aims of this study were to get a suitable design of the lateral intakes to reduce the entered depositions and also to
improve the hydrodynamics characteristics of the flow at that junctions. This study is conducted by using a numerical Software Delft3D-FM which used in predicting flows
pattern. These patterns are validated and employed in a parametric study. In this study, four models with different bed levels and slopes were presented to investigate flow separation zones at different angles of the intake entrance. In order to control the accuracy of the model in predicting the dimensions of the separated areas, the obtained resu lts were compared with the base configuration with flat horizontal bed
level of intake. Comparisons between the predicted and the base configuration
velocities at the considered sections indicate that the model captures most of the trends with sensible accuracy. The results showed that the factors which effect on the performance of the flow at the intake were bed levels, bed slopes, bed steps and intake angles. The angle of alignment is the most effective intake design attribute, where
certain angles can enhance the transverse velocity distribution at the intake entrance. Angles between 30° and 90° improve the flow of water into the intake, where θ = 30° is optimal and improves as θ goes to 90°.