Document Type : Research Paper
M. Sc. Student, Dept. of Hydraulic Structures, Shahid Chamran Universuty of Ahwaz
Professor, Dept. of Hydraulic Structures, Shahid Chamran Universuty of Ahwaz
In study of flip bucket, it is clear that the impact place of the jet with the downstream floor has the highest possibility of erosion compare to other places. Characteristics of dynamic pressure at impact place will enable us to determine the probability of scouring and its rate. It help also to determine possibility of damages to stilling basin bed and stage of particles separation from the bed which is important for design of plunge pool. In this study, the dynamic pressure as result of impact of the flip bucket jet on the bed for different flow discharge and trajectory height is measured. Analysis of the results showed that the plunge pool downstream of flip bucket jets will be effective when ratio of pool water depth to the thickness of the jet (y/Bj ) is greater than 4. Also, studies on the dynamic pressure fluctuations showed that dynamic pressure is not the maximum possible pressure over bar bed (without cushion water). The pressure fluctuation is the largest when a thin layer of cushion water is existing over the impact place. In fact, this thin layer will provide opportunities for development of vortex and turbulent flows.