Hydraulic Model Exploitation Research Of30m Hydraulic Head Francis Turbine

Computational fluid dynamics--CFD technology numerical technique can obtainmore accurate flow field of the turbine components and over-current state of theinternal flow of information for the study of hydraulic model of the hydraulic turbineperformance and stability to provide theoretical and practical basis for the successfuldesign of high performance hydraulic model of the turbine and optimize the existingturbine effective means of retrofitting.In the low-head turbine section design, high specific speed Francis turbine hashigh efficiency and high-performance wide-area, compact structure, stable operation,long life and other advantages, which is much favored by small and mediumhydropower stations. The topics for the30m water head of Francis turbine for thedesign and optimization, Application of CFD fluid simulation technology of Francisturbine inner flow analysis, Eventually developed a fine performance of Francisturbine of hydraulic model.The main research work and achievements are as follows:1、Reference the speed of light is similar to head section and the good performanceof the HL240full flow hydraulic model has been the geometric parameters for the fullflow modeling,useω=0two element theory design method to design the suitablerunner for28m-35m head Francis Turbine;2、Using Pro/E3D modeling software design high-speed HL280turbine hydraulicmodel than the original program, and Using ICEM software had full flow mesh, inorder to improve the flow of parts through the internal flow CFD simulation to predictthe performance accuracy and the accuracy of laying solid foundation;3、Aimed at the defects in conventional hydraulic design method of full spiralcasing. rational divide Hydraulic loss consists in water turbine spiral casing, Thehydraulic loss calculation model of water turbine spiral casing is built, The variablevelocity momentum optimization method to design a moment turbine spiral casingachieves reduces the hydraulic losses, enhances the spiral case performance goal ofhydraulic performance;4、through numerical simulation is done to the activities guide vanewing(positive curvature guide vane, negative curvature guide vane, symmetry guidevane) section of francis turbines and the different circumferential position on the activities guide vane and stay vane that belong to the same wing section, and analysisof its effect on turbine flow field distribution and efficiency. the result is that thepositive curvature vane can better meet the runner to flow requirement for the higherspecific speed Francis turbines; the activities guide vane and stay vane relativeposition has influence on flow field and unit performance, and obtain the bestmatching relation;5、Using CFD simulation software in the initial design of the internal flowconditions typical of a total of25calculated operating point flow with numericalsimulation, based on hydraulic model simulation results, especially the wheel, for thewhole flow of the calculation and repair type of improvement; estimate the conditionof the hydraulic model of efficiency and cavitation performance, the rest basicallymeet the design requirements and the expected effect.