Discharge Coefficient in Vertical Intakes with Additional Plates

Document Type: Research Paper


Department of Water Science Engineering, Agriculture Faculty, Tabriz University, Tabriz,Iran.


One of the causes of perturbation at vertical intakes is the happening of vortices with an air core. The vortices with an air core occur whenever the submergence of the intake is less than a critical value. Anti-vortex devices and specially plates are used to avoid the negative effects of the air-core vortices. If plates are used, then the geometry of them should be studied experimentally. Accordingly, a precise set of experiments have been carried out using rectangular plates with different dimensions. The results showed that using the vertical plates can increase the critical submergence for the same discharge rates to 51%.


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