Author(s): Yu Zhou, Jianhua Wu
Linked Author(s): Yu Zhou
Keywords: Aeration, air concentration, flow regimes, hydraulic jump, stepped spillway
Abstract: For a conventional stepped spillway, cavitation damage may occur on the vertical or horizontal surface of the steps of the spillway when the unit discharge is larger than some limit (such as 60 m3/ (s?m) ) due to the increasing flow depth and less air entrainment to the flow of the spillway. In the present work, a kind of hydraulic-jump-stepped spillway is developed and air is efficiently entrained into the flow in order to prevent cavitation damage by means of hydraulic jump aeration basin (HJAB), which is an aeration element of this stepped spillway. The physical models with different lengths and sill heights of the HJAB were designed, and the hydraulic characteristics were theoretically and experimentally investigated, including the effects of the approach flow condition, the length and sill height of HJAB on both the flow regimes and aeration effect. The results show that the flow regimes of the hydraulic jump in the HJAB significantly affect the performance of the aerated flow, and the submerged hydraulic jump should be chosen in the designs of the HJAB. Also, those flow regimes are strongly dominated by the geometry of the HJAB and the approach flow conditions and the submerged hydraulic jump could be formed even though the unit discharge reaches 110 m3/ (s?m) at the present conditions
Year: 2017