Three-dimensional Numerical Simulation Of Water Flow Through Pressure Gates Upstream And Downstream

As an important part of the hydraulic structure,the plane gate can be opened and closed in the moving water and still water to control the water storage and drainage of the hydraulic structure.In the water passage of various drainage,water conveyance,water diversion and navigation systems of the water conservancy hub,the plane gate is widely used to regulate the water level and flow rate,flood discharge,river blocking,ship transportation and so on.In recent years,the pressure head of the plane gate has been increased,the single-width flow rate,orifice size and gate size have been increased.The operation conditions brought by the opening of the gate are complicated,and the problems of dynamic stability and safety and reliability of the gate are highlighted.From the point of view of computational fluid dynamics,it is very important to use proper software to simulate the flow of flow through the gate gate,including the gate slot.In this paper,the horizontal gate flow through the gate under the above downstream pressure condition is the research object.Referring to the national code and the requirements of the hydraulic structure industry code,four kinds of gate type with different bottom edge structure are set up,many different gate opening models are established by icem software,and the ansys fluent software is used as the platform for numerical simulation.The main research contents and achievements of this paper include:(1)Based on the basic principle of computational fluid dynamics and the control equation of fluid dynamics,a large eddy simulation model is established by means of numerical simulation.(2)The icem software was selected to establish a two-dimensional model for the flow of four plane gates with different bottom edges with opening 0.16 m.Using fluent as a platform for numerical simulation,the pressure distribution,streamline and velocity vector maps of the two-dimensional flow field were obtained.Three monitoring points were set up in the flow field to observe the pressure time-history changes of the monitoring points.(3)Considering the existence of the gate slot,a three-dimensional model of flow through the gate with four different bottom gate types with opening degrees of 0.3 m,0.5 m and 0.7 m was established.Using the large vortex simulation method and using fluent as the platform for numerical simulation,the pressure distribution and streamline distribution of the 3d flow field were analyzed.Three monitoring points are set up to obtain the pressure time-history variation of the monitoring points and the characteristics of the pressure spectral density obtained by Fourier transform.The presence of funnel-shaped vortex inside the gate groove is captured,and the pressure,streamline and eddy current structure distribution of the flow field under the gate,behind the gate and on both sides of the gate groove are investigated.The hydraulic characteristics of the flow through the gate are compared and analyzed.