Akademik Veri Yönetim Sistemi
39th IAHR World Congress on From Snow to Sea, Granada, Nikaragua, 19 - 24 Haziran 2022, ss.2388-2396, (Tam Metin Bildiri)
Spillways are commonly constructed as floodwater release facilities in reservoir dams to transfer high energy water. Steps on a stepped spillway play an important role in improving energy dissipation due to the artificial roughness of the steps. This study aims to consider the influence of geometric characteristics of pooled steps on the flow patterns properties, energy dissipation performance and residual head. The localization of inception point of air entrainment is also assessed. For that purpose, different configurations and type (height and notch) are taken into account under various hydraulic conditions at different flow regime. The results showed that the flat step configuration have the best energy dissipation performance as compared with other configurations. Pool element on the steps causes some the instabilities on the center axis and sides of the steps, which causes the inception point to be moved upstream of the stepped spillway. With notched on the pool elements, their performance is improve; for example, compared with the simple pooled stepped spillway, the amount of energy dissipation increases 7.33%. The observations exhibited that the notched stepped configurations might reduce however some flow instabilities than pooled stepped configurations. Although more research is necessary on the topic, the present work shows the modified notched step configuration as the best choice for pooled stepped designs.