Experimental and Numerical Investigation of Bottom Intake Structure for Desalination Plants

Document Type : Research


1 No. 15 - 2nd floor

2 university of tehran

3 Tarbiat Modares University


One of the most important hydraulic structures which are used to divert flow is lateral intake. It can be performed by different methods, such as channels, pipes, orifices and etc. This study investigates the effects of various geometric and hydraulic parameters on bottom intake which is widely used as seawater intake for desalination plants. Observation shows that the flow velocity is higher in the square shape than in the circular shape in the front of velocity cap, while it is more at the both sides of the velocity cap in circle type. The correlation of various factors on the discharge coefficient was analyzed based on 180 physical tests by using Python code. Results show that the discharge capacity of the circle shape intake velocity cap is about 2% to 4% higher than that of the square shape intake cap. In addition, discharge coefficient of intake is affected by the approach flow Froude number and area of intake, while the height of the velocity cap has less effect on discharge trough intake. Furthermore, numerical investigation invests on flow pattern around velocity caps. Observation show that separation zone located at the back side is bigger in the square shape than in the circular shape.


Main Subjects

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