Effects of Medium Viscosity on Gas-liquid Two-phase Flow in a Multiphase Rotodynamic Pump

To understand the effects of medium viscosity on the performance, flow field and phase interaction characteristics in the multiphase rotodynamic pump, simulations with ANSYS CFX were carried out using combinations of air-water and air-crude. The drag model regarding as the most important among the phase interaction models was modified, and especially improved the predictive ability of the model under larger IGVF conditions. Due to the viscosity of crude is greater than that of water, the flow losses were larger, thus resulting in the lower efficiency and pressure rise of the pump. For the two mediums, the drag force is dominant among these four interphase forces, and the magnitude of turbulent dispersion force can be neglected relative to others, while the corresponding interphase force for air-crude is smaller than that for air-water.