An Experimental Investigation into the Effects of High Viscosity and Foamy Oil Rheology on a Centrifugal Pump Performance

This paper presents the effect of high viscosity oil and two-phase foamy-oil flow on the performance of a single stage centrifugal pump. As a part of this, the applicability of a pipe viscometer to determine the foamy oil viscosity is investigated. Unlike previous studies, a sealed fluid tank is used in a closed flow loop to allow conditioning the two-phase mixture to create foamy-oil. Furthermore, the sealed tank enables the accurate determination of the gas void fraction (GVF) of the foamy-oil under steady state conditions. The results show that up to a GVF of 38%, the foamy-oil improves head performance in comparison with the single-phase pump performance. In addition, the viscosity of foamy oil is found to be similar to the single-phase oil due to the Newtonian behavior of foamy oil. New correction factors have been developed to predict the performance of a single-stage centrifugal pump handling foamy oil.