Analysis of flow in spillway and energy dissipator of Glevard dam using numerical methods

By increasing in construction of large dams, the needs for increasing the safety of flood discharge structures are necessary in design. Overflow spillway and sky jump as a terminal structure downstream of spillway are frequently used in dams. In the present study, the spillway and sky jump of Glevard dam are modeled by Flow-3D software and their hydraulic parameters are studied. Verification tests revealed that RNG turbulence model is the most convenient turbulence model. Sensitive analysis showed that the more suitable mesh size is 0.6 meter. Analysis of hydraulic characteristics of flow showed that the occurrence of cavitation at the end of chute is more probable. In the sky jump, the occurrence of positive pressure prevents of cavitation. The changes in geometry of bucket such as the angle of lip and the radius of bucket are investigated. Increasing the angle of lip about 20 degrees, increases the length of jet until 40 meters.