Jet trajectory of flow-separating slot-type flip bucket

Abstract

Abstract A flip bucket is a common element used to dissipate energy for release works. For the purpose of avoiding excessive scour and flow choking, the slot-type flip bucket was developed. In this paper, a flow-separating slot-type flip bucket (FSSFB) is proposed on this basis, which can divide the approach flow into three branches by dividing walls, and thus generate two small, completely separated jets resulting in better energy dissipation performance and reduced scour. Based on model tests, the jet trajectory of the FSSFB is investigated. Considering the local head loss from the flow passing the dividing walls, the take-off velocity is amended for calculating the jet trajectory using the projectile method. Based on fitting analysis, the head loss coefficient is a function of the relative width b/B, the relative angle θ/β of the slot and the Froude number Fro of the approach flow. Finally, an empirical relationship for the head loss coefficient is provided, and the error in the calculation of jet trajectory is less than 10% for the FSSFB.