某水库泄洪排沙洞水力特性及排沙效果研究

Research on Hydraulic Characteristics and Sediment Diversion Efficiency of Flood Discharging and Desilting Tunnel of Reservoir

针对某水库引水发电洞前泥沙淤积的问题,在某引水发电洞附近新增泄洪排沙长隧洞,通过水工模型试验研究了不同工况下排沙洞的水力特性(沿程压力、流速、流量、流量系数、空穴数等),并对比试验值与设计值,验证了排沙隧洞设计的合理性。以塑料沙为模型沙,通过河工模型试验,确定了冲沙漏斗的大小,比选了排沙方案,给出了排沙洞洞口布置的合理位置,使发电洞达到"门前清"的效果。研究成果为类似工程提供参考。

Aiming at the sedimentation problems of power generation tunnel, a newly built long flood discharging and desilting tunnel of a certain reservoir nearby a power generation tunnel was selected as the study object. The hydraulic characteristics of the tunnel under different working conditions were studied by hydraulic model test. These characteristics including the pressure along tunnel, flow velocity, discharge, flow coefficient, and cavitation number, etc. A comparison of experimental value with the design value was made, and the design rationality of the tunnel was verified. Sediment model experiment was performed by using plastic sand as the model sand. Through the model test, the size of the sand funnel was determined, and the desilting schemes were compared. The reasonable layout of the flood discharging and sed- iment tunnel was given, and the effect ＂door clean＂ of power tunnel was obtained. The research results provide references for the similar projects.