Author(s): Tantao Song; Jun Deng; Wangru Wei

Linked Author(s): Jun Deng

Keywords: Wedge-aerator; Velocity distribution; Dynamic water cushion; Numerical simulation

Abstract: Step type aerator is a common aerator with simple shape and small disturbance to flow. However, the problem of cavity backwater is obvious at low Froude number. This paper introduced a wedge-shaped aerator arranged at the pressure outlet, which could divide the water flow into upper and lower layers and form a cavity behind the wedge aerator. Compared with the traditional aerator, the lower layer flow has a certain velocity, which could bring some backwater generated by the flow collision to the downstream to optimize the cavity backwater problem. The three-dimensional numerical simulation method is used to study the flow characteristics after the wedge aerator. The results show that the flow behind the wedge aerator will appear velocity stratification after the intersection. The increase of wedge aerator arrangement height and Froude number can increase the relative velocity of the lower layer flow, make the lower layer flow have water carrying capacity and weaken the backwater. Combined with the cavity shape and velocity distribution characteristics under different conditions, the backwater can be effectively eliminated by increasing the arrangement height of wedge aerator to more than 0.1 of the pressure outlet when the Froude number of water flow is low. The research could improve the research on wedge aerator and provide help for the design of aerator at low Froude number.

DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p1192-cd

Year: 2023