The effect of deflectors mounted inside a cylindrical wedge wire screen capturing water on the velocity distribution around its surface

Abstract

Modern water intake systems face numerous challenges related to both operational efficiency and environmental protection. Key aspects are the protection of the intake from pollution and mechanical damage as well as the protection of ichthyofauna. In response to these needs, innovative solutions are being developed, such as wedge wire screens, which are placed in surface water intakes. This paper presents the results of a study carried out on a screen that was placed in a hydraulic channel. The proposed design solutions involved a screen model and two interchangeable deflectors that were mounted inside the screen. The deflectors differed in the arrangement and size of the holes while maintaining the same degree of perforation. These solutions were studied in detail experimentally with a specialised measuring apparatus. It was shown that the maximum velocities were significantly reduced and the inflow velocities were equalised around the screen due to the installation of the deflectors. It was also observed that 
a deflector with non-uniform openings slightly better equalised the intensities of the incoming water flows than a deflector with equal-sized perforations.