Sediment erosion is one of the main reasons for the failure of hydraulic components of a Pelton turbine. Especially in sediment season

sediment concentration increases greatly and the process of sand-carrying three-phase flow on the surface of the runner bucket is complicated

so the erosion problem is usually more severe. The Pelton turbine at the Zixia hydropower station in Tibet

planned for construction

is examined in the present work as a case study. This paper focuses on numerical simulations of its flow process of sediment particles on the bucket surface

using the Mansouri erosion model and the Euler-Lagrange method

based on its measured sediment characteristics data provided by the design institute. The characteristics of sediment particle flow and erosion distribution over the bucket surface under high sediment concentration in sediment season are examined. The numerical predictions of surface erosion distribution agree well with previous measurements in literature. The predictions show the bucket erosion concentrates near the water outlet edge of the root and the cutout edge of the bucket. The highest similarity occurs between the distributions of sediment erosion and the impact number

so the impact number imposes a great effect on sediment erosion.