A new model for predicting liquid loading in inclined gas wells

Liquid loading remains a major challenge in gas well production, especially in inclined wells where gravitational effects intensify fluid accumulation. This study presents a mechanistic model for predicting the critical liquid-carrying velocity, incorporating non-uniform film thickness, droplet entrainment, and wellbore inclination. The onset of liquid loading is defined by zero wall shear stress, marking film reversal. A momentum balance yields a velocity - thickness correlation, corrected by geometric and entrainment effects. Model validation through laboratory experiments shows an average relative error of 4.99%, while field data from 20 gas wells confirm 85% prediction accuracy. Results indicate that higher liquid flow increases film thickness and gas core density, necessitating higher gas velocities. Larger pipe diameters shift flow distribution and reduce interfacial shear, and the critical velocity peaks at a 38 degrees inclination. The model offers enhanced predictive capability and a theoretical basis for optimizing liquid unloading in deviated wells.