Abstract:
To find a better numerical method to simulate the cavitating flows in the centrifugal pumps, the influences of three widespread cavitation models (Zwart-Gerber-Belamri model, Kunz model and Schnerr-Sauer model) were verified on the numerical predictions of the centrifugal pump performances. The simulations were executed with three different flow coefficients, from 0.082 to 0.122. Subsequently, the numerical results obtained by different cavitation models were compared to the measured values, respectively. The prediction accuracy of Kunz model were higher than the other two cavitation models with the design flow coefficient and the small flow coefficient, and the simulation results under the Zwart-Gerber-Belamri model with the large flow coefficient was close to the experimental data. In addition, the cavitating flows of the centrifugal pump obtained by Kunz model with φ=0.102 was analyzed, and the bubbles generated at the suction side of blade near the leading edge at first and then expanded to the outlet of impeller with the decreasing of cavitation number; the decreasing total pressure coefficient occurred in the upstream of the impeller passage principally, while the downstream approximately remains unaffected with the development of cavitation; the load on the blade was greatly affected by cavitation.