Effect of axial matching between inducer and centrifugal pump suction chamber on cavitation performance

摘要

According to the design requirements of a booster centrifugal pump, the full three-dimensional numerical calculation of the model pump is carried out based on the RNG k-e turbulence model and the Rayleigh-Plesset cavitation model to analyze the influence of the axial matching of the inducer and the suction chamber (i.e. the degree of the axial extension of the inducer into the suction chamber) on the cavitation performance of the centrifugal pump. Five sets of centrifugal pump design schemes were selected respectively with the ratio of the axial direction of the inducer into the suction chamber and the axial distance of the inducer hub were 0 (original scheme), 1.6%, 3.2%, 4.8%, and 6.4% to compare the distribution of axial static pressure of the inducer and the suction chamber, the variation of cavitation characteristics, head (energy of a fluid per unit weight obtained by working with a pump expressed in the form of height) and efficiency of the centrifugal pump, the distribution of bubbles in the inducer and the impeller, and the static pressure distribution law of the inducer in the runner. According to the results, what are illustrated are that the cavitation performance of the centrifugal pump can be improved by inserting the inducer into the suction chamber to a certain extent, and the cavitation performance is better with the increase of the axial indentation degree, but it tends to be stable after reaching a certain degree. At the same time, it was found that the vapor bubbles in the inducer and the impeller first appeared in the low pressure region at the inlet rim of the blade.