Pressure fluctuation characteristics of gas-liquid two-phase flow in multiphase pump
SHI Guangtai1,2, LIU Zongku1,2*, LI Helin1,2, YANG Xi1,2
1. Key Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu, Sichuan 610039, China; 2. School of Energy and Power Engineering, Xihua University, Chengdu, Sichuan 610039, China
Abstract：To perform a thorough investigation into the effect of inlet gas void fraction(IGVF)on the flow structure and pressure fluctuation characteristics in multiphase axial-flow pump, the transient flow field and pressure fluctuation characteristics in a multiphase axial-flow pump were numerically simulated at 5%,10% and 15% IGVFs based on the standard k-ε turbulence model by employing ANSYS CFX. Then, the variation rules of internal flow field structure, frequency domain characteristic, and pressure fluctuation coefficient with IGVFs were analyzed and summarized. The results shown that when the IGVF exceeds a certain extent, the pressure fluctuation was weakened. Meanwhile, the dominant frequency amplitude has a significant effect on the pressure fluctuation. Under the gas-liquid two-phase condition, rotor-stator interaction is still the main cause for pressure fluctuation. Specially, the dominant frequencies of pressure fluctuation in the impeller and diffuser were 11 and 3 times of the impeller rotational frequency, respectively. Further, the maximum amplitude of the dominant frequency and pressure fluctuation coefficient appeared near the rotor-stator interface. The research results can provide some reference for structural optimization, hydraulic design and fatigue analysis of multiphase axial-flow pump.
