Comparison of Energy Dissipation between Nappe and Skimming Flow Regimes on Stepped Chutes

For the last decades, stepped spillways have become a popular method for handling flood releases. The flow regime over a stepped chute can be either a nappe flow or skimming flow regime. The energy dissipation of both flow regimes are analysed. The results are compared with experimental data. For long chutes where uniform flow conditions are reached, higher energy dissipation takes place in a skimming flow regime. But, for short channels, nappe flows would dissipate more kinetic energy than skimming flows