Head loss estimation for water jets from flip buckets

Yavuz, Cüneyt
Dinçer, Ali Ersin
Aydın, İsmail
Water jet issued from flip bucket at the end of the spillway of a dam can be a threat for the stability and safety of the dam body due to subsequent scour at the impingement point. However, a strong jet from the flip bucket interacts with the surrounding air and develops into an aerated turbulent jet while the jet impact and scouring effect is reduced significantly. Aeration of the jet, at the same time, cause head losses along the trajectory. An experimental study is conducted to measure the trajectory lengths and investigate the effect of water depth in the river on the dynamic pressures acted on the river bed. The trajectory lengths with and without air entrainment are calculated using empirical equations and compared with the measurements. Head losses due to air entrainment are determined using the difference of the trajectory lengths with and without aeration, based on the projectile motion theory. Numerical simulation of the flow over the spillway, along the flip bucket and the jet trajectory is made and the results are compared with the experimental data. It is observed that trajectory lengths obtained from experiments, numerical simulation and empirical formulas are comparable with negligible differences. This allows us to combine alternate approaches to determine the trajectory lengths with and without air entrainment and estimate the head losses accordingly
Citation Formats
C. Yavuz, A. E. Dinçer, and İ. Aydın, “Head loss estimation for water jets from flip buckets,” pp. 48–57, 2016, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/84330.