Numerical analysis of rotor-stator interaction in a high-head pump-turbine at turbine mode
Year: 2016
Type: conference-paper
Abstract: Rotor stator interaction (RSI) between runner blades and guide vanes in pump-turbines may cause unstable vibrations and serious damage to hydraulic system. In order to investigate this problem, five turbine operating points with different guide vane openings were selected for three dimensional calculations of steady flow and unsteady flow, and the water blocking phenomenon caused by flow separations on the pressure sides of runner blades and formed by RSI has been analyzed. The obtained results show that under the same unit speed conditions, the smaller the guide vane opening, the more obvious the flow separations on the pressure sides of the runner blades, the larger range of water blockage was formed by RSI. Flow separations on the pressure sides of the runner blades in certain negative incidence range would not formed water blockage under the effect of RSI, and the range of negative incidence was closely related to the guide vane opening. The forming of water blockage had obvious periodicity, and rotated with the runner. At a runner blade passage, it presented on a water blocking area disappear, the next water blocking area grow, the collapse of water blockage caused impact to the guide vanes, and led to the vibration amplitude of guide vane increased greatly. The primary cause of instability appeared in high-head pump turbine at no-load turbine condition was also obtained.
Source: HAL
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W3045367345