A Numerical Method for Predicting Liquid Loading of Condensate Gas Wells

Abstract

Abstract. Condensate gas wells always experience three phases (gas–water–condensate oil) flow in the wellbore; the interaction between each phase is more complicated, which aggravates the liquid loading and causes severe production decline. In the optimization of gas well production, accurately predicting the onset of liquid loading is of critical importance. While significant efforts have been dedicated to modeling liquid loading behavior, mechanistic models capable of balancing practicality and accuracy in describing the complex flow dynamics of gas–water–condensate oil three-phase systems in vertical wells remain scarce. First, the Euler–Euler multifluid volume of fluid (VOF) model is applied to simulate the liquid film flow behavior, and the Schiller–Naumann and Brackbill-continuum surface force (CSF) models calculate the interactive effects between gas–water–oil three phases. Then, experiments are conducted to validate the numerical results, and a close agreement was observed between the numerical and experimental results with respect to pressure gradient and critical velocity. Finally, the field application results show that the numerical method not only improves model accuracy to over 90% but also eliminates human bias, providing a robust tool for liquid loading diagnosis in condensate wells.