Hydraulics of stepped spillways with different numbers of steps

This paper describes the study of two physical models that were built to investigate the energy dissipation and flow regimes for different discharges over stepped spillways with different numbers of steps. These physical models had a general slope of 19·2% and had 12 and 23 steps respectively. Experiments were carried out for a wide range of discharges. The hydraulic parameters of the flow over the models were measured and the energy dissipation of flow was also calculated. Results showed that the 12-step model dissipated more energy than the 23-step model. However, the flow regimes that occurred in the 23-step model were considered more acceptable than in the 12-step model. The experiments showed that energy dissipation at lower flow rates were similar in both cases. However, in the skimming flow regime at higher discharges, energy dissipation was about 12% less in the 23-step model than in the 12-step model.