Two-Phase Flow Modeling of Inducers

Abstract

Inducers, which are classified as axial flow pumps with helical path blades, are used within rotary gas separators commonly used in electrical submersible pump installations. A two-phase flow model has been developed to study the inducer performance, focusing on head generation. The proposed model is based on a meridional flow solution technique and utilizes a two-fluid approach. The model indicates that head degradation due to gas presence is a function of flow pattern. The effect of flow pattern diminishes when the void fraction is greater than 15 percent since the centrifugal force dominates the interfacial drag force. In this case, the two-phase flow can be approximated as a homogeneous mixture. The model also suggests that a liquid displacement correction is needed when phase segregation occurs inside the inducer. The new model significantly improves the ability to predict separation efficiency of a rotary gas separator over existing models. Hydrocarbon-air and water-air experimental data were gathered to validate the new model.