Numerical Simulation on Backwater Downstream of Aerators in Spillway Tunnel with Ultra-Low Frounde Number Flow

Abstract:

The backtracking of flow occurs easily in cavity of aeration step in spillway tunnel with a gentle bottom slope and ultra-low Frounde number, and this influences the intake of air, so combined with the spillway tunnel of Chang heba Hydropower Station, four bodily form of aeration steps are chosen to be studied by both numerical simulation and model test based on κ-ε turbulence model, they are continuous aeration step, U-type aeration step + local steep slope, continuous aeration step + circular arc type steep slope and continuous aeration step + ogee curve steep slope, the results show that, the downstream bottom slope of aeration step with suitable ogee curve or circular arcs can efficiently inhibit the backtracking of flow in continuous aeration step, and can efficiently eliminate hydrops in cavity and in the same time can improve the efficiency of aeration. Usually, the results of bottom slope with an ogee curve are better than that with a circular arc.

• Periodical: Applied Mechanics and Materials (Volumes 444-445)
• Pages: 539-543
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.444-445.539
• Online since: October 2013
• Authors: Li Qiang Chen, Jun Xing Wang, Yu Ting Chen
• Keywords: Arc Bottom Slope, Hydrops in Cavity, Numerical Simulation, Ogee Curve, Ultra-Low Frounde

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