Study On Bottom Edge Of Plane Steel Gate In Deep Hole Based On Numerical Simulation Of Fluid-solid Coupling

The plane gate is one of the earliest and most widely used kind of gates in water power engineering. Because of the complexity of the structure and working conditions of the plane gate, there exists many security problems in the application. For example, vibration and cavitation erosion often occurs when the plane gate is opened, closed or part-opened. Sometimes, the gate even get damaged when the phenomenon is serious.The auto oscillation characteristic of plane gate is the internal causes of vibration, and the negative pressure and pulse pressure from water flow is the main external cause of cavitation erosion and vibration. Bottom edge affect not only the vibration characteristics of the gate, and there is also a greater influence on the flow regime. Therefore, based on the fluid-solid coupling numerical analysis method, the plane steel gate with submerged water jump as the research object, establish the gate model with different bottom edge type, and compare the influence on gate with different types. The conclusions provide scientific basis for rational arrangement of gate, and has an important practical significance for the project.The main work and conclusions of this paper are as follows:(1) Parameterized models are established using the commercial software ANSYS12.0 with ANSYS WORKBENCH as the operation platform. Numerical simulation of the two-dimensional model of water jump is done by the module of FLUENT. And the hydraulic characteristics of water flow with different bottom edge type are analyzed.(2) Based on the actual running of tailrace gate in a hydropower station, established the three-dimensional one way fluid-solid coupling model of the flow-gate system. The influence analysis of bottom edge to gate structure was completed. The up lift force and down pull force got increased compared with the original model. In the forth revised schemes, the problem of negative pressure on the plane gate got obvious improvement.(3) Considering the fluid-solid coupling effect, the self-vibration characteristic of plane gate is analyzed. The conclusion shows that the influence of the bottom edge structure types with only front rake to the dynamic characteristics is not apparent. While the influence of the bottom edge structure types with both front rake and back rake is serious. The self-vibration frequency of gate structure is decreased obviously with the fluid-solid coupling effect.(4) Combining with projects, modify the structure type of bottom edge on the basis of the original model. The static and dynamic properties of plane steel gate were studied with different schemes. The rationality of standard is verified.