Prediction Analysis on the Sediment Erosion and Energy Dissipation Inside a Three-Stage Centrifugal Pump

Centrifugal pumps are essential to modern marine engineering systems for fluid transport. This study is to analyze the typical failure causes of sediment erosion and energy dissipation in a multi-stage centrifugal pump with different blade installation angles α using numerical simulation approach and on-site testing. Three different schemes with α = 0°, 10.85°, and 21.7° were designed. The installation angle of the blade influenced sediment erosion and energy dissipation through three key aspects: turbulent flow, particle motion, and wall roughness. Turbulent and friction dissipation, which are related to the blade angle and sediment erosion, are the leading causes of the pump failure. The symmetrical blade installation, turbulence intensity, particle impact velocity, and wall friction inside the unit were the highest, resulting in the most severe turbulence loss, wall loss, and sediment erosion under this scheme, with the maximum friction loss being 320 W·m−3·K−1. Complex turbulence intensifies the intensity of particle motion, with the maximum sediment erosion rate E = 0.000052 kg·m−2·s−1. Compared to Plan 1 and Plan 3, the performance can be improved by more than 20% and 23%, respectively. There was a positive correlation between the friction loss and erosion rate. The research presented in this study provides a novel perspective on the operation of a pump to prevent sediment erosion failure.