Fluid dynamics optimization and energy performance analysis of centrifugal pump based on automatic optimization system

An automated three-dimensional optimisation framework for centrifugal pumps is developed based on the direct design method, integrating parametric modelling, automatic meshing, CFD simulation, design of experiments (DOE), and nonlinear optimisation. Seventeen geometric parameters of the impeller and volute are parameterised, and their effects on pump head and efficiency are evaluated through orthogonal experimental design, sensitivity analysis, and correlation analysis to identify key parameters and coupled influences. The framework integrates CFturbo 10.3 for parametric modelling and ANSYS 18.1 for automatic meshing and CFD simulation. A centrifugal pump is selected as a case study to validate the proposed framework. Based on DOE results, a Non-Linear Programming by Quadratic Lagrangian (NLPQL) algorithm is employed to further optimise the hydraulic model under head constraints with efficiency as the objective. Comparative analyses between the original and optimised designs show that the optimised pump achieves average increases of 14.63% in head and 10.74% in efficiency over the operating range. Detailed flow field analyses are conducted to investigate the internal flow mechanisms associated with performance improvement. The optimised impeller exhibits more uniform inlet flow distribution, a significant reduction in backflow intensity at the impeller outlet, and increased average relative flow angle across different operating conditions. These flow structure improvements indicate enhanced energy conversion and reduced hydraulic losses, confirming that the performance gains are closely linked to the optimisation-induced modification of internal flow characteristics.