Experimental Study on Initial Stage Diversion of Yangfanggou Hydropower Station

The Yangfanggou Hydropower Station takes the single cofferdam with tunnel diversion as the diversion mode.In order to further understand the flow conditions of initial stage diversion and ensure safety of cofferdam and the dam construction,the initial stage diversion model experimental research is conducted.Through the model test,it measures the discharge capacity,flow pattern,cavitation number of diversion tunnel,downstream flow velocities and river bed roughness.The safety of water passing of diversion tunnel is verified.According to the experimental results,the inflow conditions of weir crest elevation of cofferdam and diversion tunnel entrance is optimized,which provides guidance for diversion design and construction organization in initial stage.