Abstract: The ski jump energy dissipator has been most widely used in the energy dissipation of high dam, yet optimizations should be made according to the unique characteristics of different projects. The outlet structures of three different dam types investigated by Yangtze River Scientific Research Institute are taken to illustrate the research achievements. Different arrangements of energy dissipator have been made for the three dam types. First, for the centripetal concentration of discharge flow at Geheyan gravity arch dam, a combination of the asymmetric shrink of flaring pier at the surface spillway, asymmetric contraction of the recurved narrow slit at the deep outlet, and plunge pool, is arranged. Second, for the erosion and siltation in the energy dissipation area of the asymmetric narrow valley at Shuibuya concrete face rockfill dam, narrow slit flip buckets are arranged in a cascade. Third, to solve the erosion problem of spillway plunge pool in the case of maximum power dissipation at Goupitan double curvature arch dam, differential flip bucket and flow-separating dentated sill for surface outlet combined with collision of different jet angle at the middle outlet are applied. Practices of flood discharging at the projects indicated that these new types of energy dissipator successfully solved the energy dissipation problem for the projects, and thus could be referential for alike ski-jump energy dissipation of high dams.

Key words: energy dissipation of ski jump type  ,   flaring pier  ,   narrow slit flip buckets ,    plunge pool