Method for Selecting Centrifugal Pump Impeller Outlet Angle Based on Calculation of Centrifugal Pump Impeller's Hydraulic Loss

At present, during the process of the design of centrifugal pump impeller, blade outlet angle has a larger range of selection. However, the outlet angle has great influence on the efficiency of the centrifugal pump. In order to improve the efficiency of the centrifugal pump, we established the function relationship among the flow rate, rotational speed, leaf number, specific speed, outlet angle, impeller design parameters and the efficiency of hydraulic which based on the pump impeller hydraulic loss. We built the performance prediction program for the pump which Q is 100 m³/h, H is 34 m, n is 2 900 r/min and mapped the relationship between blade outlet angle and the efficiency of hydraulic diagram. The graph shows that the Impeller hydraulic efficiency is highest, when the number of blades is 5, β₂ is 29°, and k₀ is 4.2. In order to ensure the correctness of this method, we designed the impeller according to the design parameters and use FULENT software to predict the numerical simulation of the internal flow field. The result shows that the impeller's efficiency can reach 89%, which proves that this method can be used to design high efficiency centrifugal pump impeller.