期刊名称：IOP Conference Series: Earth and Environmental Science
印刷版ISSN：1755-1307
电子版ISSN：1755-1315
出版年度：2019
卷号：240
期号：2
页码：1-8
DOI：10.1088/1755-1315/240/2/022057
出版社：IOP Publishing
摘要：The maximum and minimum water head difference of bulb turbine is only a few meters to ten meters, and the performance is highly sensitive to the change of water head, especially in low head operation, the bulb turbine performance deteriorates and vibration intensifies, this seriously affect the normal operation of the power station. Therefore, considering the free surface and water gravity, a numerical method is adopted to study the performance of prototype bulb turbines at different water head, by analysing the distribution of flow parameters with water head in hydraulic turbine, it is revealed that the stress of blade is uneven and the cause of cavitation and vibration at low head operation. The results show that: with the decrease of water head, the cavitation performance of the runner becomes worse, the low pressure area moves from the suction side to the pressure side of blade; the water torque of the guide vanes and the runner blades in different positions is different, which could cause the guide vane and blade angle asynchronism during adjustment; with the decrease of water head, the torque difference generated by the blades at different positions on the rotating shaft of the hydraulic turbine increase, the blades experience dynamic stresses, It threatens the strength of the blade and the stable operation of the unit.
