Experiment of energy dissipation and scour protection below flood-releasing works of Longkaikou Hydropower Station

Longkaikou Hydropower Station has a large flood discharge;and its dam is located at a narrow valley.The discharge structure is arranged in the main river bed with the hydropower station next to it.Energy dissipation and scour protection are the main problems for this kind of project.The paper has done some researches on energy dissipation effect of overflow slab and mid-discharge-orifice,the linkage between the water flow after its energy dissipation and the downstream water,the erosion of downstream river bed and bank and the water flow of fluctuation of station tailwater by using hydraulic model test through many experimental schemes.The paper has rendered the optimal layout scheme and the outlet structure types through comparing the interaction between energy dissipation and power generation so as to offer references for bank protection.The study has some effects on designing project that has characteristic of large discharge and narrow river valley in other model experiments.