Unsteady CFD simulation for bucket design optimization of Pelton turbine runner

28th IAHR symposium on Hydraulic Machinery and Systems

Kumashiro, Takashi^1 ; Fukuhara, Haruki^1 ; Tani, Kiyohito^1

Basic Engineering / Hydraulic Laboratory, Hitachi Mitsubishi Hydro Corporation, 3-2-1 Saiwai, Hitachi, Ibaraki, Japan^1

关键词: Computational loads;    Design optimization;    Numerical investigations;    Observations and measurements;    Simplified analysis;    Turbine efficiency;    Turbine performance;    Unsteady cfd simulations;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/49/2/022003/pdf
DOI  :  10.1088/1755-1315/49/2/022003

来源: IOP

【 摘 要 】

To investigate flow patterns on the bucket of Pelton turbine runners is one of the important issues to improve the turbine performance. By studying the mechanism of loss generation on the flow around the bucket, it becomes possible to optimize the design of inner and outer bucket shape. For making it into study, computational fluid dynamics (CFD) is quite an effective method. It is normally used to simulate the flow in turbines and to expect the turbine performances in the development for many kind of water turbine including Pelton type. Especially in the bucket development, the numerical investigations are more useful than observations and measurements obtained in the model test to understand the transient flow patterns. In this paper, a numerical study on two different design buckets is introduced. The simplified analysis domain with consideration for reduction of computational load is also introduced. Furthermore the model tests of two buckets are also performed by using the same test equipment. As the results of the model test, a difference of turbine efficiency is clearly confirmed. The trend of calculated efficiencies on both buckets agrees with the experiment. To investigate the causes of that, the difference of unsteady flow patterns between two buckets is discussed based on the results of numerical analysis.