Three-dimensional numerical investigation of flow through screens as energy dissipators

Abstract

Screens, perforated units to dissipate energy in hydraulic structures, are investigated numerically in this study. These units are part of a physical setup exposed to supercritical flows, normally created by sluice gates. The interaction of perforated screens and supercritical flows results in local complex three-dimensional flows, which can be analyzed by the application of RANS-based flow equations. The most important controlling parameters include supercritical Froude number between 2 and 10 and screen porosity of 40% and 50%. Numerical water surface profiles and energy dissipation are validated by the author’s experimental data. This paper derives a set of equations in terms of depth ratio of the hydraulic jump through the perforated screens and assesses the effect of baffles on energy dissipation. This study seeks a proof-of-concept for the application of the RANS-based technique for further application of the result to real hydraulic structures in due course.