Abstract:By using empirical correlations, basic geometry parameters of impeller were obtained. The impeller profile was adjusted according to given flow cross section area distribution and wrap angles distribution; and the position of the splitter blade was determined according to the relationship between the splitter blade deviation angle and Wiesner slip factor. Based on this method, using the same design parameters (head, capacity, rotation speed, etc) with different factors, four different low specific speed centrifugal pump impellers with different splitter blades (75%, 65%, 55%, 45% long blade length) were designed. By using RANS equations with RNG k-ε turbulence model, three dimensional turbulent flow fields of the designed impeller channels were calculated and analyzed. The effects of four different splitter blades on velocity distribution, pressure distributions along the flow channels and hydraulic performance of centrifugal pump impellers were studied. The results show that the hydraulic head of impeller can be improved by adding splitter blades; long splitter blades will increase hydraulic loss and fraction loss and the increased amount of hydraulic head increases as the splitter blade length decreases. With properlyselected design parameters and properlypositioned splitter blades, the flow in the pump can be improved and its hydraulic performance can be enhanced.
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