Title: Experimental Survey of Energy Dissipation in Nappe Flow Regime in Stepped Spillway Equipped with Inclined Steps and Sill
Abstract: Stepped spillway increases the hydraulic resistance against flow by using of step-made spillway floor and when the flow of water passing on steps, a significant part of energy dissipates and also reduces the risk of cavitation. In this experimental research, in order to increase the energy dissipation of stepped spillway, Steps has a reverse gradient and in other part of this tests in addition to create a reverse gradient in the steps at the same time the sill is also installed on the edge of the steps. Height, thickness of the sills is considered variable. The results show that in both Nappe Flow Regime and Skimming Flow Regime Change of gradient, sills height, thickness are effective to increase the energy loss but the effect of these parameters on the Nappe Flow Regime is much greater than Skimming Flow Regime. By analyzing the results of the experiments and compared with results from other studies, the research showed that the method used in this study has a better energy loss than other methods used in prior researches.