Researches On Reservoir Sedimentation And Sediment Erosion In Hydro-turbine:Case From The Xiaowan Dam

Sediment monitoring in river is an important part of reservoir management. Engineering practice has proved that it is necessary to conduct water sediment transporting, physical and chemical composition of sediment and changing regime of sediment in reservoir. Simultaneously, water and sediment will cause erosion in hydraulic turbine, leading to turbine anomaly during operation.This study took the reservoir of Xiaowan Hydropower Plant as an example. According to the actual situation of Xiaowan Hydropower Station Reservoir area, design sampling site and analysis method. In 2015, according to the design scheme, the author carried out the sampling and detect thems. Analyse Sediment yield, sediment characteristics and water quality of Xiaowan Hydropower Station Reservoir Area.The results show that:the Xiaowan Hydropower Station of incoming sediment is mainly composed of aluminum silicate, followed by Fe2O3, K2O, Cao, MgO, Na2O. The main chemical elements O, Si and Al of suspended sediment and bed sand occupy more than 80% of the total amount of the element. In addition to the content of manganese (Mn), the heavy metal elements were all lower than 1ppm.Water temperature changes basically according to air temperature annual change. Water body has been weak alkaline, but the difference is not large. The redox potential of the water in the dam is almost higher than that in the front of the dam, especially in August. The dissolved oxygen of the water body in the dam is slightly higher than that of the dam, and the salinity has been maintained at 0.2ppt.Educe deposition of Xiaowan reservoir in 2015 by use the Brune model. The value is 11445456.605T. Educe abrasion of water turbine in 2015. The annual average erosion rate was 6.05mm/kh.Research results can provide the basis for help design management of sediment of Xiaowan Hydropower Station, also provide technical reference for other hydropower station.