Study On Hydraulic Load Calculation And Anti - Abrasion Of Impact Area Of ​​Bottom Flow Energy Dissipation

In dam pivot arrangement, the energy dissipation is especially important for the layout of buildings, by the high water head and flow rate per unit width of large flood discharge energy dissipation problem is very outstanding. Traditional energy dissipation work to ensure the safety of the flood discharge energy dissipation, the effect of energy dissipation and the good influence on ecological environment security, on this basis, the research is applied to the high water head and flow of a single phone type big drop underflow energy dissipation. Drop the underflow energy dissipation work is at the entrance of a stilling basin, the stilling basin base plate excavation form the drop down, constitutes a certain longitudinal vertical depth and type of stilling basin drop. But because of the drop, water flow into the stilling basin, water submerged jet formation, up and down in the mainstream and the strong form vortex shear turbulence energy dissipation, drew the mainstream from the stilling basin base plate at the same time, reduce the stilling basin and the moving velocity in the hydraulic indexes such as water pressure, and can effectively solve the traditional underflow energy dissipation work of stilling basin and the moving velocity in the strong water pressure, the impact of protection is difficult problem.Drop the underflow energy dissipation type tools have high energy dissipation efficiency, into the ChiLiu stable state, and the advantages of small flood discharge atomization, therefore can effectively expand the underflow energy dissipation work range of engineering application.Type based on the national natural science foundation of "drop the underflow energy dissipation work research on the structure of flow hydraulic characteristics LiTi (project number:51169008), based on the hydraulic model test research, combining with theoretical analysis, different type of drop underflow energy dissipation work flow hydraulic characteristics were studied.In this paper, the main research results and conclusions are as follows:Based on hydraulic model test results, the bottom flow submerged jet flow structure, the velocity distribution in the stilling basin water movement under calculation, the dynamic water pressure distribution calculation; After the camp spiral vortex area hydraulic characteristics and movement laws, On the basis of creating water flow regime partitions in impact zone of bottom-flow dissipation with step-down floor, I put forward an empirical formula of dynamic water pressure in impact zone. Analyzing the distribution diagram of dynamic water pressure in impact zone with matlab, the influence of different factors on dynamic water pressure is concluded. Combining the distribution diagrams and free turbulent jet theory, it shows the most vulnerable area to damage and abrasion and analyzing the reason of damage and abrasion. Based on the gravity similarity criterion of a reservoir engineering project, I derive relevant parameters of empirical formula to verify the feasibility of the theory, then combined with bottom velocity to achieve the abrasion resistance strength in impact zone of concrete. In conclusion, this text is hoped to have certain guiding significance to partition on the floor of dissipation and select concrete materials of the stilling basin reasonably for engineering project.