In order to study the stability of the reverse power generation of a pumping station unit in the East Route of the South to North Water Diversion Project, the full numerical simulation of the flow channel was carried out to study the pressure fluctuation and stress distribution in the reverse power generation. Monitoring points in three sections of guide vane inlet, runner inlet and outlet were set up. The results show that the time domain diagram of pressure fluctuation at the inlet and outlet of the axial flow pump shows periodic variation under the reverse power generating condition. The frequency of pressure fluctuation is influenced by the frequency of runner and concentrated at low frequency. The flow pressure fluctuating in the middle and edge of the runner inlet is obvious. The maximum pressure fluctuation occurs at the middle of the runner outlet. The amplitude of the pressure fluctuation is nearly 3 times the outlet edge of the runner, and it is nearly 2 times the middle and edge of runner inlet. At the impeller outlet, the pressure fluctuation increases from hub to rim. The results of fluid-solid coupling show that the total deformation of the blade is mainly distributed in the inlet side of the blade, and the deformation increases gradually along the wheel hub to the wheel edge, and the stress mainly concentrates on the blade pressure surface and the root of the suction surface, and the maximum equi-valent stress appears at the impeller root of the suction surface of the blade. The maximum equivalent stress value does not affect the life and damage of the runner unit in the safety range of blade material.
Journal of Drainage and Irrigation Machinery Engineering
axial flow pump
reverse power generation