Experimental and Numerical Investigation of Rotor–Stator Interaction in a Large Prototype Pump–Turbine in Turbine Mode

In recent years, large-capacity, high-head pump–turbine units have been developed for pumped storage power plants to effectively utilise water energy and store large amounts of electricity. Compared with the traditional Francis turbine unit, radial distance between trailing edge guide vanes leading runner blades unit is smaller, so rotor–stator interaction corresponding pressure fluctuations in vaneless space are more intense. The high amplitudes frequencies induced by (RSI) become main hydraulic excitation source structures may cause violent vibration fatigue damage structural components, seriously affect safe operation units. this paper, RSI a mode studied detail means site measurement full three-dimensional unsteady simulations. results RSI-induced analysed experimentally numerically. accuracy numerical calculations verified comparing measured results, variation law deeply analysed. show that affected wake vane, rotating runner, low-frequency draft tube, asymmetric characteristics incoming flow spiral case, shows significant differences spatial position. findings investigation an important valuable reference design station. It recommended inclined inlets reduce avoid operating under partial load long periods time risk fluctuation severe on structures.