Study On The Influences Of The Bucket Lip To The Nappe And The Flow Field In Cushion Pool

In this paper,based on the theories and practical engineering experiences of the trajectory energy dissipation, employed k ??turbulence model in which the VOF model has been introduced, the influences of the bucket lip to the nappe and the flow field in cushion pool have been studied in this paper. And the numerical simulation results have been verified by the results of the physical model.By comparing the hydraulic characters of four different hybrid types of flip bucket (including high and low style, hybrid type, and slit-type flip bucket), the flow pattern of the nappe, the velocity and aeration distribution of flow, the efficiency of energy dissipation of the nappe, the velocity distribution in the water cushion pool and the pressures on the floor have been detailedly analyzed. In the four different types of flip buckets, the hydraulic characters of slit-type flip bucket is the optimum, the nappe fulliest spreads in the vertical and horizontal range, aeration volume is the largest, the efficiency energy dissipation is the highest, the pressures on the floor of cushion pool are the smallest, and the flow velocity in the surface of cushion pool floor is the lowest. The slit-type flip bucket can meet the need of Nankang river hydropower station hydraulic design, so it is recommended in the paper.In the paper the dominant mechanism of energy dissipation of the nappe has been elaborated, the important role of the aeration in improving the efficiency of the nappe energy dissipation has been discussed, and the disciplines of design flip bucket type has been summed up, and the feasibility that numerical simulation technology is an important method of the release work design has been verified, this paper is an example of application of FLOW-3D software in hydraulic design.