Numerical Analysis of Internal Flow and Cavitation Phenomenon for a Mixed-Flow Pump with RANS-based CFD Methodology

Abstract

Computational fluid dynamics were widely used to analyze the hydrodynamic behavior of the mixed-flow pump, and reliability and accuracy were validated by comparing the results with the experimental data. In this study, complicated cavitation phenomena has been implemented by the RPE model. As a result, it has been found that the overall error was 6.8% through comparison with the performance curve of the analysis value and the experimental data. Recirculation occurred near the shroud at the impeller inlet when the flow rate was 6 m3/min. In addition it was found that non-uniform pressure drop occurred at the impeller outlet when the flow rate was 9 m3/min. Through vortex visualization technique, the onset position of the tip leakage vortex captured at the blade tip region of suction surface. By comparing with vortex structure and cavitation region, it was found that tip leakage vortex suppresses cavitation phenomenon at the blade tip region of suction surface.