Study of multiphase flow and sediment erosion of large Pelton turbine bucket in sandy river

Sediment erosion presents a significant challenge in the development of high-head Pelton turbines operating in sandy rivers. This study investigates the hydrological sediment conditions of a large Pelton turbine in Tibet, China, utilizing a model turbine derived from preliminary design data (single unit > 500 MW class). The gas–liquid–solid three-phase transient flow characteristics within the model turbine are analyzed. The study calculated three working conditions with different sediment particle sizes and concentrations, analyzed the bucket erosion conditions, and conducted erosion tests on the model turbine under these three conditions. By integrating experimental data with numerical simulations, a mathematical model for sediment erosion in the model turbine bucket of this power station is developed. This model accurately predicts erosion in the actual Pelton turbine of the research power station and other similar stations. The findings offer a theoretical foundation and technical support for forecasting erosion in large-scale Pelton turbine buckets at this facility.