Numerical Study for Improving Energy Dissipation over Stepped Spillway by using Different Configurations on Steps

Abstract

The stepped spillway is a hydraulic structure used steps to decrease the energy in the stilling basin that can reduce the cost. The numerical analysis is widely used currently. In this study, flow 3d software was adopted in numerical analyses. The simulation model used RNG k~e turbulence model with VOF. Several configurations on steps are applied, these configurations included adding the half balls baffles and sills, convex half ball and holes on the steps. The numerical model was performed, depending on a physical model of Salmsi (2009) to know the effect of these configurations on the rate of energy dissipation. The number, location, and diameter of half balls and holes are considered in the numerical simulation. The results showed that using three half balls (one on the inner edge and two at the outer edge of steps) gave higher energy dissipation about 54% in skimming flow regime, the increase is estimated at 57% than the flat step.