STEPS NUMBER EFFECT ON HYDRAULIC PARAMETERS OF FLOWS IN STEPPED SPILLWAYS

F. LEBDIRI, A. SEGHIR, A. BERREKSI

Abstract


Spillways are one of the most important parts of dams. There are several types of spillways, but they all play the same role. The flow through these structures is quite complicated hydraulically. The main focus of this study is the free surface flow in stepped spillways. Thus, the objective is to determine the influence of the steps number on the hydraulic parameters of the flow through this type of spillway. Taking into account the complexity of the equations of motion governing the flow through these structures, the use of Ansys-Fluent software was chosen in order to carry out the desired numerical models. It is to be noticed that this software is based on the finite volume method. The basic equations of the phenomenon treated are those of an incompressible fluid given by Navier-Stokes, while for modelling the turbulence the k-ε equations were used. The VOF model coupled with Level-Set was also used in order to take into account the biphasic flow characteristics. The influence of the steps number on the energy dissipation, on the water level, and also on the shear stresses acting on the walls was analyzed.


Keywords


Stepped spillways, Turbulent flow, Navier-Stokes, k-ε model, Energy dissipation, VOF, Level-Set.

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References


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Available at SSRN: https://ssrn.com/abstract=3373179

or http://dx.doi.org/10.2139/ssrn.3373179

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