Mechanistic modeling of two-phase flow in deviated wells

Gas-liquid two phase flow in deviated wellbore is the foundation of choosing ways of oil pumping and production optimization and it can be resolved well by simply adding an efficiency to the vertical well model. It is also a problem which has not been solved completely in theory for a long time. All the flow patterns in the deviated wellbore were described as bubbly, dispersed bubble, slug, churn, annular and mist flows according to the analysis of the studies published. Mist flow predicting model was developed and flow-pattern map was obtained. Pipe diameter condition prediction in bubbly flow, new methods of predicting pressure drop of slug flow and mist flow were included. The entrainment fraction in annular space was also defined. 35 groups of field data of 28 wells were used to validate the models. Results show that the absolute average percentage error is 7.093%, which is almost the same with that of Beggs-Brill and Ansari methods. It is of benefits of no convergence and high adaptability.