Multi-Parameter Optimization Design of Axial-Flow Pump Based on Orthogonal Method

The axial-flow pump is a widely used piece of general machinery which consumes large amounts of energy. In this study, an axial-flow pump with the specific speed of 536 is firstly designed and experimentally measured; then, the orthogonal method is employed to conduct the energy performance optimization. Five optimization parameters, including hub control point, hub stagger angle, shroud stagger angle, camber angle and centroid position were set with four levels. Sixteen individual pumps were designed according to the orthogonal method; then, a numerical simulation was implemented to obtain the energy performance and flow pattern. Results showed that the shroud stagger angle has the maximum influence on the pump head and efficiency, and the hub stagger angle and camber angle are also very important. At a design point of flow rate 70 kg/s, the efficiency of the optimal pump is 86.29%, which improved by 2.05% in comparison with the baseline pump. The pressure gradient of the optimal pump from blade inlet to outlet becomes more fluent than that of baseline pump, and the low-velocity region of the optimal pump at the blade head shrinks, compared to that of the baseline pump.