Today several dams are equipped by the stepped spillways because of efficient for energy dissipation and of high contribution to the stability of these structures. The air-water flow on stepped spillway can prevent or reduce the cavitation damage. The air entrainment starts where the boundary layer attain the free surface of flow; this point is called “point of inception”. The objective of this paper is to study the characteristics of flow at stepped spillways such as velocity profile, pressure field and effect of step height in risk of cavitation by numerical method. In this resarch, the Ansys fluent computational fluid dynamics (CFD) is used to simulate water flow down stepped spillway and turbulence parameters are calculated by standard k −ε model. The volume of fluid (VOF) model is utilised to track free surface of flow. The found numerical results agree well with experimental results.


inception point, flow field, Ansys Fluent, VOF Model, Stepped Spillway, Standard k −ε Model.

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