Effects of bucket type on flood discharge atomization
摘要
The aim is to solve the problem of increasing the energy dissipation rate during the flood discharge with aggravating the downstream atomization, and to explore the influence of different flip buckets on atomization of downstream. Based on the physical model test, the downstream nappe wind distribution, the splash-water distribution, the hydraulic characteristics of trajectory nappe and the scour pattern were studied. The research shows that:① The downstream nappe wind speed of the asymmetrical tongue-shaped bucket, the standard tongue-shaped bucket and the curved surface bucket are generally larger than that of continuous bucket. ② For the asymmetrical tongue-shaped bucket, on the left side of spillway axis, the splash intensity is greater than that of the right sides. the maximum difference of the rainfall intensity between the left and right sides is 5.625 g/(m2·min). but for the distribution of curved bucket is opposite, on the right sides of spillway axis, the splash intensity is greater than that of the left sides. the maximum difference of the rainfall intensity between the left and right sides is 45.125 g/(m2·min).③ With the increase of the distance between the control point and the impinging piont, the number and the volume proportion of the large water droplets decreased sharply; with the increase of trajectory angle, both the trajectory nappe width of continuous bucket and tongue-shaped bucket are increase; and the depth of scour pool decreases with the decrease of trajectory angle. ④ When adopting the flip bucket whose curved surface is attached to the proper side wall, which can reduce the atomization influence; and the erosion damage of downstream can be reduced by increasing the trajectory angle.