Sediment flushing upstream of large orifices: An experimental study
| Autor: | Kourosh Qaderi, Majid Rahimpour, Mohamad Reza Madadi |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Hydrology
010504 meteorology & atmospheric sciences 0208 environmental biotechnology Flow (psychology) Orifice plate Sediment 02 engineering and technology Restrictive flow orifice 01 natural sciences Flow measurement 020801 environmental engineering Computer Science Applications Hydraulic structure Modeling and Simulation Erosion Electrical and Electronic Engineering Instrumentation Geology Body orifice 0105 earth and related environmental sciences |
| Zdroj: | Flow Measurement and Instrumentation. 52:180-189 |
| ISSN: | 0955-5986 |
| DOI: | 10.1016/j.flowmeasinst.2016.10.007 |
| Popis: | Due to the constricting and localization of flow by orifices, these hydraulic structures are commonly used in dams and water impoundment reservoirs to flush deposited sediments. They are also one of the most important flow measurement structures. In this study, the flow characteristics at upstream of a large circular orifice located at the wall of a water reservoir, in the case that the sediments were accumulated behind it, was investigated. The experiments were performed at the hydraulic laboratory of Shahid Bahonar university of Kerman, in a model of rectangular reservoir. The experiments were performed in two parts. First, the flow behavior during the scour development at upstream of the orifice and the extent of sediment erosion due to the orifice flow was investigated. Next, a semi-confined structure was located at the upstream of orifice to increase the sediment removal efficiency. The effect of the geometrical characteristics of structure on the dimensions of scour hole was determined. It was observed that the interactions of water, sediment and structure generated strong vortices upstream of the orifice, which caused the lifting and sweeping away of a large amount of sediment from the reservoir and let to formation of a semi-cone hole upstream of the orifice. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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