Hydraulic Model Exploitation Of High Specific Speed Francis Turbine

In recent years, with the computational fluid dynamics-CFD technology matures, the development of the turbine model and the internal flow field analysis of the applications are more and more widely. CFD numerical technique can obtain more accurate flow field of the turbine components and over-current state of the internal flow of information for the study of hydraulic model of the hydraulic turbine performance and stability to provide theoretical and practical, basis for the successful design of high performance hydraulic model of the turbine and optimize the existing turbine effective means of retrofitting.In the low-head turbine section design, high specific speed Francis turbine has high efficiency and high-performance wide-area, compact structure, stable operation, long life and other advantages, which is much favored by small and medium hydropower stations. Because of this, developed excellent performance of high specific speed Francis turbine hydraulic model, can be more reasonable, adequate and effective use of water resources, the potential resource advantages into economic and social benefits, is of great significance.Head for the lower section of the subject development and utilization of water resources, than the speed of light is similar to head section and the good performance of the full flow hydraulic model has been the geometric parameters. Using Pro/E 3D modeling software and ICEM software design high-speed HL300 turbine hydraulic model than the original program, and had full flow mesh, in order to improve the flow of parts through the internal flow CFD simulation to predict the performance accuracy and the accuracy of laying solid foundation. CFD simulation, the use of Reynolds averaged Navier-Stockes equations and the RNGκ-εturbulence model, using SIMPLEC algorithm, the initial design of the internal flow conditions typical of a total of 25 calculated operating point flow with numerical calculation and simulation, for simulation; based on hydraulic model simulation results, especially the wheel, for the whole flow of the repeated calculation and repair type of improvement; estimate the condition of the hydraulic model of efficiency and cavitation performance. The main innovations of this paper:1. AutoCAD provides two-dimensional section of a Francis turbine blade wooden model diagram, to import Pro/E generates three-dimensional graphics, data transfer between the more convenient, accurate and intuitive expression.2. Imports for the blade edge and the crown into the intersection of the problem can not be directly used on the crown leaves and virtual extension of the method, the upper section of the blade curve to extend, draw close to good performance than the speed of blade inlet edge and runner band after line cut leaves, in order to get a good blade inlet conditions and flow conditions. And flow analysis based on the simulation results to adjust airfoil, to ensure the smooth blade surface smoothness.3. Design a good performance of the turbine runner and the hydraulic model of flow parts.