Study On Combined Energy Dissipator With X-Shape Flaring Gate Pier In Shatuo Hydropower Station

The contracted jet technology of flaring gate pier is a new dissipater and has been created by our country. So far, that is thirty years and it has played a better role in many large and medium-sized water conservancy and hydropower projects. With the construction of the high head and large discharge structures, some projects shows that about 70 percents spillway surface of traditional flaring gate pier can't discharge and exits such issues, for example, not enough discharge, oversized impacting pressure, and so on. Because of the triage area at the bottom in X-shape flaring gate pier, to solve the above problems plays a very good effect.The Shatuo hydropower station is ninth of the main stream in Wujiang River. This hydropower station is a integrated project for the main power generation, both shipping, flood control, irrigation and other benefits. The dam height is 106m, the checking flood discharge is up to 32020m3/s, the unit-wide discharge is 305m3/s﹒m and the water head on the weir is for 27.33m. As such, this hydropower station has the characteristics with high head and large unit-wide discharge and the dissipater issue are obvious. The mainly researches about this paper are as follows:(1)Analyzing the hydraulic and energy dissipation characteristics of the X-shape flaring gate pier. Elaborating flood characteristics of Shatuo hydropower station in detail. By analogy about some projects, showing that it is feasible, as the combined energy dissipater with X-shape flaring gate pier is adopted by Shatuo hydropower station for solving the flood dissipater problems.(2)Through some projects and experiments, comparing X-shape and Y-shape flaring gate pier for the size, flow characteristic, and so on. Revealing X-shape flaring gate pier takes more advantages than Y-shape flaring gate pier for Shatuo hydropower station.(3)Carrying on revising and optimizing experiments of the type about X-shape flaring gate pier. Through analysis and comparison, selecting the 8 plan as the last optimizing type, with parameters of contraction rateεfor 0.33 and the angleθfor 24.44 degree. The hydraulic model tests with scale of 1:100 are carry out and observe the discharge capacity , flow and water lines, average pressure, velocity distribution, erosions of the lower reaches and fluctuating pressure on the bottom of plate in stilling basin. The results show that optimizing type of X-shape flaring gate pier has a good effect of energy dissipation, the length of stilling basin reduce by 31 percents than the beginning plan, the plate height raise 9m, amount of works are cut and investments projects are saved.In words, that Shatuo hydropower station adopts X-shape flaring gate pier solves the discharge and dissipation issues, for example, the high head and the large unit- wide discharge, and so on. Its application designs are referenced for similar projects.