Calculation of Pressure Distribution over Flip Buckets

Flip buckets are used as terminal structures at the end of chute spillways or bottom outlets. Flow after a bucket is issued in the form of a jet to a location far from the bucket where it impacts the river bed and forms a plunge pool. Energy of high speed flow is dissipated in the plunge pool and flow enters the river with a low velocity. Design of buckets and calculation of dynamic pressures over a bucket is usually done by physical model studies or design charts based on field measurements. Physical model studies are expensive and modification of the model takes time and is also difficult. Design charts are also developed based on limited field measurements. In the present study dynamic pressures over flip buckets are calculated using a numerical model. To simulate the free surface high speed flow over buckets, FLUENT computer code is employed. The numerical model was verified using existing experimental data. Free surface location, as well as pressure distribution over buckets were compared with measurements and very good agreement was obtained. The effect of Froude number and ratio of flow depth to bucket radius was also investigated. The results of analytical models for pressure distribution over buckets were also analyzed, discussed and compared with numerical data.