Hydraulic study of two phase flow on low-gradient stepped spillways

Authors

• Ali Akbar Hekmatzadeh
• Seyed Mehrab Amiri
• Soroush Papari

Abstract

Recently, low gradient stepped spillways, which can be constructed on the embankment dams, have been getting high attention owing to their easy implementation. A few numerical researches have been conducted to simulate the flow hydraulic on stepped spillways. In this study, the air water flow was simulated using two-phase mixture model. Six models of turbulence including Eddy viscosity, k-ε, RNG k-ε, k-ω, SST k-ω, and ω-RSM were applied to describe the turbulence of flow. According to the results of numerical and experimental tests, it was found that k-w and ω-RSM are superior to describe the turbulence of flow. Moreover, the mixture two-phase model described the experimental data successfully. In addition, the effects of spillway slope, flow discharge, and step height in the amount of energy dissipation were examined. It was concluded that the energy dissipation increases with a rise in the step height and a reduction in the slope and the flow discharge. In the unit discharge of 2.34, the energy dissipation increased from 39 to 50 percent with decreasing the spillway slope from 26.6 to 8.9 degree.

Keywords

• Low gradient stepped spillway
• Two-phase flow
• Turbulence modeling
• Reynolds stress model

20.1001.1.20086377.1395.9.28.7.8

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