A high-speed debris flow sliding into a reservoir can cause a huge disaster. Consequently, predicting landslide movement accurately and its potential interaction with water is crucial. This paper developed a computational model based on a two–layer two–phase material point method (MPM) to simulate surge waves generated by granular landslides on an erodible slope. By comparing granular landslide on a rigid and erodible slope, the effect of the slope erodibility on the process of landslide movement and the waves generated is investigated. The model takes full account of the large deformations, fluidisation and settlement of granular material in soil–water interactions. The numerical model is validated by comparing the simulated results with experimental data. The influences of internal friction angle, density, elastic modulus, Poisson ratio and dilatancy angle on wave height are also studied. The validated model was then used to investigate the surge waves generated by dry and saturated granules sliding along a rigid and erodible slope. The results show that both the erodible slope and saturated granular slide can increase the first wave crest height generated by the landslide.

In this paper, the selection process of specific speed, specific speed coefficient and rated speed of a unit of a high head and large capacity pumped storage power station is systematically analyzed. According to the selection principle of the unit speed of high head and large capacity pumped storage power station, a suitable range of rated speed of the unit is recommended. First of all, through the in-depth study of the comparative speed, according to the statistical formula of the specific speed of the pump and turbine working conditions at home and abroad, the specific speed range of the characteristics of the power station is determined to ensure the efficiency and stability of the unit. Then, according to the selection of rated speed, a comprehensive technical and economic comparison is carried out, and the influence of technical parameters and economic influence of different speed schemes is analyzed. The speed selection of high head and large capacity pumped storage power station units in this paper provides a scientific basis for improving the overall performance and economic benefits of the power station.

With the rapid development of renewable energy, pumped storage power station as an important regulating power supply, its construction scale continues to expand. As the core equipment of pumped storage power station, the rationality of the rated head selection of pump turbine directly affects the stable operation and economic benefits of the power station. In this paper, four different rated head schemes are proposed to select the rated head of the turbine of a pumped storage power station, and the influence of rated head on the stable operation of the unit is discussed. Through the detailed comparison of the technical parameters of each rated head scheme, the performance of the different schemes in the aspects of operation stability and economy is analyzed. The key parameters of rated head were optimized by multi-objective optimization method combined with actual engineering requirements. The results show that reasonable rated head of pumped storage power station is the premise of stable operation of turbine, and this paper provides an important theoretical basis and practical guidance for the design and operation of pumped storage power station.