Internal Flow of Contra-Rotating Small Hydroturbine at Off- Design Flow Rates

28th IAHR symposium on Hydraulic Machinery and Systems

Shigemitsu, Toru^1 ; Takeshima, Yasutoshi^2 ; Ogawa, Yuya^2 ; Fukutomi, Junichiro^1

Institute of Science and Technology, Tokushima University, 2-1 Minamijyosanjima-cho, Tokushima-city

770-8506, Japan^1

Graduate School of Advanced Technology and Science, Tokushima University, 2-1 Minamijyosanjima-cho, Tokushima-city

770-8506, Japan^2

关键词: Alternative energy;    Contra-rotating;    Contrarotating rotor;    High-efficiency;    Internal flow condition;    Numerical flow analysis;    Partial flow rate;    Small hydro power;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/49/10/102008/pdf
DOI  :  10.1088/1755-1315/49/10/102008

来源: IOP

【 摘 要 】

Small hydropower generation is one of important alternative energy, and enormous potential lie in the small hydropower. However, efficiency of small hydroturbines is lower than that of large one. Then, there are demands for small hydroturbines to keep high performance in wide flow rate range. Therefore, we adopted contra-rotating rotors, which can be expected to achieve high performance. In this research, performance of the contra-rotating small hydroturbine with 60mm casing diameter was investigated by an experiment and numerical analysis. Efficiency of the contra-rotating small hydroturbine was high in pico-hydroturbine and high efficiency could be kept in wide flow rate range, however the performance of a rear rotor decreased significantly in partial flow rates. Then, internal flow condition, which was difficult to measure experimentally, was investigated by the numerical flow analysis. Then, a relation between the performance and internal flow condition was considered by the numerical analysis result.