4.Fluid mechanics

[14001-04-02] Characteristics of Three-dimensional Turbulent Flow around Traditional Crib Spur Dyke (Proceedings of Symposium on Applied Mechanics)

*Hao Zhang¹, Natsuki Uehara¹, Hiroshi Takebayashi², Yasuhiro Takemon², Yuko Ishida³ (1. Kumamoto University, 2. Kyoto University, 3. Setsunan University)

Keywords:Traditional river works, Crib spur dyke, Local flow, Turbulence characteristic

This paper presented an experimental study on turbulent flow characteristics around a traditional Japanese crib spur dyke (Seigyu) under flood scenarios.The results showed the flow acceleration due to spur dyke overtopping and mainstream narrowing, the velocity reduction in the spur dyke wake and the flow separation due to the intensification of lateral flow. Due to the unique shape of the spur dyke, local downward and upward flows as well as complex distributions of turbulence kinetic energies and Reynolds stresses were observed in the vicinity of the spur dyke. The crib spur dyke enhances flow diversities and promotes exchanges of mass and momentum in both the vertical and the lateral directions.