A simple model for annular two-phase flow in wellbores - Texas A&M University (TAMU) Scholar

Annular flow is associated with production from both gascondensate and geothermal wells. Oil wells also experience it during high-GOR production. The current mechanistic modeling approach entails estimation of film thickness before computing frictional pressure-drop as gas flows past the wavy-liquid film surrounding the pipe wall. This study probes to discern this film thickness and its impact on pressure-drop computation in wellbores producing steam-water, gas-condensate, and gas-oil mixtures. Computational results show that the most likely value this dimensionless liquid-film thickness is less than 0.06 in annular flow. For such thin-film thickness, the computed friction factor is only slightly higher than that estimated with smooth-channel assumption. When the homogeneous model is used to compute pressure gradient by ignoring the wavy liquid film on frictional pressure-drop, good agreement is achieved with field data and those of a mechanistic model. Copyright 2005, Society of Petroleum Engineers.

A simple model for annular two-phase flow in wellbores Conference Paper