Study On The Hydraulic Characteristics Of Slit-type Bucket Based On Aerated Water Flow

Slit-type flip bucket is widely used in the energy dissipation design of water resources and hydropower engineering. Because of high velocity of narrow slip constriction flow, strong three-dimensional characteristics, complex factors and so on, the universal relevant hydraulic calculation in theory has not yet been put forward. The calculation is mainly based on hydraulic model test and relevant empirical formula. In the construction of high-head, long-spillway flow or flow tunnel, since high-speed water from the surface and bottom is fully aerated, some slotted flip bucket of water contains a high volume segment, even aerated uniform flow; while in the hydraulic model tests under normal conditions which results in the reduced scale model effect, the flow aerator segment of slit-type flip bucket is very low. There is no adequate study about fully aerated flow's effect on slit-type flip bucket hydraulic characteristics. It is necessary to study the hydraulic characteristics of the flip bucket slit aerated flow.The focus of research is the characteristics of the narrow joint bucket hydraulic. Using hydraulic model test method, adjusting the flow of water in the bucket by the way of artificial aeration, we study on the influence of different water content on the hydrau lic characteristics of the narrow slit bucket, and reveal the inherent relation bet-ween the water content and the related factors of water flow.The main results are as follows:(1)In flow non aerated conditions, studied three different slit contraction size(contraction ratio ?of 0.2, 0.25, 0.3) and different flow conditions(Fr =5.7 ~ 8.8) of the water lines,wall and flood water pressure,picked from the tongue of the relevant laws.(2) When the flow is uniform flow of water and gas, the narrow slit-bucket in the conditions of different doped concentrations of gas dynamic water pressure, side wall of the water line, picked from the tongue. Reveal the aerated flow concentration of narrow slit-bucket influence laws about related hydraulic characteristics.(3) Through the narrow slit-bucket at comparative test and comprehensive analysis on different concentrations of aerated and non-aerated flow conditions associated hydraulic characteristics. The research results have important practical significance to enrich and perfect the design theory of the narrow slit bucket design, which can improve awareness of the hydraulic characteristics and the laws in the water fully aerated conditions.