Correlation Analysis between Blade Number and Blade Load of Nuclear Main Pump Impeller

Abstract

For research the relationship between blade number and load distribution law of the nuclear main pump, a model pump with a ratio of 0.4 is taken as the research object. The nuclear main pump with different impeller blade number is subjected to a three dimensional steady numerical simulation by using the RNG k- ε turbulence model. The results indicate that when the number of guide vane blade remains constant, the pump head increases gradually and the efficiency of the pump increases firstly and then decreases with the increase of blade number. Therefore, only through the reasonable matching of the blade number and the guide vane, the pump hydraulic performance can reach the optimum value. At the same time, the variation gradient of blade load becomes slower with the raise of impeller blade number, and the load peak point is close to the blade outlet edge, in which the dynamic pressure load will have a greater impact on the pump performance. When the dynamic load coefficient and the static load coefficient are distributed in a certain proportion and the peak point of the dynamic load coefficient is located in the middle of the blade streamline, the pump will have better performance.