Optimization method for sediment erosion performance of centrifugal pumps with varying specific speeds based on inverse design

Sediment erosion on flow-passing components of centrifugal pumps in Yellow River pumping stations under high sediment-laden flow poses significant operational risks. Inverse problem design is an effective optimization method with the core step of predefined blade load distribution, yet the correlation between its load distribution strategies and erosion characteristics of pumps with different specific speeds (ns) remains unreported. This study optimized five centrifugal pumps with ns of 90, 114, 131, 151, and 205 using inverse problem design, exploring the effects of load distribution schemes on erosion resistance and summarizing a generalized load distribution method. Results show the optimal schemes: Scheme II (ns = 90), Scheme III (ns = 114, 131, 205), and Scheme I (ns = 151). Compared with the original pumps, the optimized ones reduce the maximum blade erosion rate by 9.29%–73.17%, shrink severe erosion areas, and improve erosion resistance. With increasing ns, severe erosion areas shrink, sand-phase volume fraction on blade surfaces increases, and sand-phase velocity decreases. By analyzing load control point distribution laws in optimal schemes, a correlation between load control point values and ns was established via the least squares method, forming an accurate inverse problem-based load distribution method that effectively shortens the optimization cycle.