Development Hydraulic Model Scheme Of 1500M Flood Peak Multistage Energy Recovery Pump And Turbine

Energy is an useful resource can be directly or through conversion provide the human need. Energy is an important foundation for national economic development, but also an important material basis for people of production and protection of life. With the development of economy, the energy issues has already become the focus of the world. Energy recovery pump and turbine can further recycling mechanical energy be contained in the working fluid to reduce energy loss, so as the energy recovery pump and turbine applications increases, people have higher requirements for its performance.The computational fluid dynamics - CFD technology has matured in recent years, the applications of it in the fluid machinery model development, research and the internal flow field analysis are more and more widely. The CFD numerical simulation can obtain the fluid machinery interior flow field distribution and various overflow parts interior flow regime information accurately, provides the technical support for studying the fluid machinery performance, and is the effective means of designing the high performance fluid machinery model successfully and optimizing to the existing fluid machinery.At present, the design theory of energy recovery hydraulic pump and turbine is not mature. Just the principle of work, the energy recovery hydraulic pump and turbine is equivalent super low specific speed turbine, change the energy of working fluid into rotating mechanical energy. But compared with the multistage energy recovery hydraulic pump and turbine, it has similarities with multistage pump.Traditionally,consider the reversal of the pump as energy recovery hydraulic pump and turbine, but flow state and running condition of the reversal of the pump is not fully comply with the energy recovery hydraulic pump and turbine, therefore performance relatively poor. So development of high performance energy recovery hydraulic pump and turbine can be more fully and effectively recycling energy resources, the potential resource advantages into economic and social benefits, has a certain academic value and practical significance.This essay design and optimization the energy recovery hydraulic pump and turbine that head period 1500m, using CFD simulation technology to explore the internal flow of it. Calculation with continuity equation, Renault time-averaged N-S equation as the control equations. Turbulence model was used standard k-εdouble equation turbulence model to make equations closed, and velocity and pressure iteration-correction is carried out with SIMPLE scheme, discrete used a second-order accuracy of implicit difference format. Numerical calculations as done by used in the article, not only the velocity and pressure distribution patterns can be gained, but proved the design method is scientific, and provide the basis for future optimization design. Eventually developed a relatively fine performance hydraulic model scheme of nine stages energy recovery pump and turbine.The main research contents and creative achievements are as follows:1.Based on the existing geometric parameters, the series of the energy recovery hydraulic pump and turbine that head period 1500m were determined to be eight, nine and ten grades.Made hydraulic design calculation of the corresponding series runner and flow components by using monistic theory and Francis turbine and multistage pump design theory.2.Runner and flow components of energy recovery hydraulic pump and turbine has been designed are modeled in three-dimensional solid by using Pro/E software. The three-dimensional solid is meshed unstructured grid by ICEM and Gambit software. Compared advantages and disadvantages of ICEM and Gambit software divided grid. The problem of easily having a hole or broken surface is solved in the grid division stage and proposed the method of combine ICEM and Gambit software to divide mesh.3.The numerical simulation is done to the initial design of hydraulic model,and the relevant parts'geometry size is repaired and improved through the analysis of the numerical simulation results. Through compared the simulation results of different series energy recovery hydraulic pump and turbine, determined the most suitable pump and turbine series is nine stages.4.Through the analysis of the numerical simulation on the large flow rate condition, design flow rate condition, small flow rate condition to the nine stages energy recovery hydraulic pump and turbine, researched relationship between recovery efficiency and flow rate,and the internal flow is given. The results show that the pressure, velocity distribution of the design condition are best.