Numerical Analysis The Hydraulic Characteristic Of Symmetry Curved Surface Slit-type Bucket

With the rapid development of high dam construction in China, the problem of energy dissipation about outlet structure has been increasingly prominent. Practice shows that Slit bucket applied for energy dissipation has broken through the traditional model of energy dissipater on Conventional width nasal candy.by using contraction of the both sides of bucket wall, the current will be longitudinal diffusion,and the longitudinal diffusion of water will exacerbate water flow turbulent to make its full aeration, improve the energy dissipation, So as to achieve the purpose of reducing the scouring of downstream riverbed . At present, Slit bucket applied for energy dissipation has been successfully used in high water head of discharge water buildings at home and abroad,and become a kind of efficient energy work. However, due to the complexity of flow , the influence of incoming flow and downstream boundary conditions, there is no more perfect analysis method and a unified experience formula on the design and apply of Slit bucket applied for energy dissipation , still mainly dependent on hydraulic model test results. In recent years, along with the improvement of computer calculation capacity, simulation and research on Slit bucket applied for energy dissipation by using numerical simulation has become a new trend, using method of the combining of a numerical calculation and physical model test to study the the hydraulic characteristics and energy dissipation of effect of Slit bucket applied for energy dissipation will future research.In order to further know the hydraulic characteristics of Slit bucket applied for energy dissipation , on the basis of research achievements which has been collected at home and abroad, the old ferry spillway as the research target, the research methods combining with three-dimensional numerical simulation and the physical model test has been applied for a more in-depth research . Physical model adopts 1:7 0 hydraulic model,do experimental analysis for the hydraulic characteristics of different flow conditions, get the basic rules of Hydraulic characteristics such as the pressure distribution,the form of water tongue in air, downstream riverbed scouring, demonstrate the rationality of the shape parameter selection work for Slit bucket on the old ferry spillway applied for energy dissipation, further enrich research achievements of academic field work on Slit bucket applied for energy dissipation. Mathematical model adopted RNGk~εturbulence model,made use of VOF method to trace the free surface, took Standard hexahedral structured grid and use large fluid mechanics calculation software Flow3D to do three dimensional numerical simulation for the old ferry spillway, obtained distribution regularity of hydraulic parameters such as the water surface lines, pressure and velocity ,and compared the numerical simulation results with the physical model test, the results were basically identical.This article mainly aims at the three kinds of bucket type which put to use in bank spillway design of the old ferry hydropower station, three dimensional numerical simulation has been used, through comparing ,analysing and summarizing the characteristics of three kinds of bucket type, flow characteristics of surface posted kok narrow gap has been highlighted ,to Provide a reference basis for a final design. At the same time, to reveal the effect about complex structure characteristics of surface posted kok narrow gap to convection , four major parameters has been selected, each parameter will selecte four groups plan to contrast and analyse,then the rule of influence about four major parameters to Water tongue form will be work out.Meanwhile, The candy pick Angle,trajectory distance and diffusion dissipation of Water tongue has been carried on the beneficial discussion.Research also shows that it is practicable to using the mathematical model on simulation research about flow characteristics of Slit bucket on the old ferry spillway applied for energy dissipation, the research work has accumulated some experience on using mathematical model for flow characteristics of Slit bucket applied for energy dissipation and lay a good foundation to carry out in-depth research work for the numerical simulation of Slit bucket applied for energy dissipation.