Based On The Length Of The Blade Francis Turbine In The Cfd Study

The project supported by the National Science Foundation of China(Grant No.XXXXXX) and the Provincial Science Foundation of Yunnan(Grant No.XXXXXX). Numerical simulation of three-dimensional turbulent flow through Francis turbine with long and short blades, long blades or short blades is (CD turbine,C turbine and D turbine) conducted on the basis of Reynolds equations closed byκ-εturbulent model with general coordinates. The prototype of calculation is HLA351.The results show that the detail of flow field in each Francis turbine can be well predicted. And systematic study of internal flow was carried out. This paper receives these points'achievements:(1) According to practical parameters of the Francis turbine HLA351,it are successfully established to three-dimensional geometric model of CD, C, D Francis turbine using software PRO/ENGINEER, and it can be quickly changed to the position of guide vanes with different conditions.(2) According to the characteristics of flow passage components of turbine, sub-block grid was used successfully so that mesh of spiral case, distributor, runner and elbow draft tube is high-quality.(3)Numerical simulation of three-dimensional turbulent flow for the three turbine runner at different operating conditions are conducted on the basis of Reynolds equations closed by realizableκ-εturbulent model with different general coordinates. From analysis in energy performance and cavitation performance,it can be found that turbine performance have been influenced to types of blade,and in the same circumstances, hydraulic performance of the runner with long and short blades is better than conventional runner, and velocity and pressure distribution of the runner more reasonable. It can be concluded that the results are able to provide an important guideline for the hydraulic design of Francis turbine or its optimization.(4) Flou information is successful deliver between flow passage components of turbine by the interface to achieve CD turbine static and dynamic coupling. (5) Three-dimensional steady turbulent flow and unsteady flow for CD Francis turbine at general operating condition were simulated based on parallel computing with RNG k-e turbulence model and N-S equations.(6) From the calculation results, a detailed analysis and the pressure pulse of various components of the CD turbine were carried out,and it can be found to pattern of pressure fluctuation generation and transmission in the turbine.