Numerical simulation of anti-vortex devices at water intakes

Abstract

The formation of vortices above the submerged discharge intakes of water reservoirs is undesirable as they can suck surface debris and air into the discharge pipework. In the present work, a numerical investigation was performed on the performance of an anti-vortex device at the water intake. The numerical simulation of the flow field around a free-surface vortex was verified with experimental data, with good agreement found on radial velocity and vortex type. The lateral shape of the anti-vortex device was defined by the modelled inflection points in the vertical profile of the radial velocities. The numerical simulation presented here may also be helpful in gaining a deeper understanding of determining the intake depth required to avoid air-entraining vortices in reservoirs. It may also be useful in studying the behaviour of free-surface vortices in the presence of anti-vortex devices.