Partition Perforation Optimization for Horizontal Wells Based on Genetic Algorithms

Abstract

Summary Because of heterogeneity in permeability along horizontal wellbores, early water breakthrough and rapid water-cut increase are always observed in high-permeability completion intervals when a uniform perforating scheme, as a common practice, is applied throughout the wellbore. Optimization on perforation parameters along horizontal intervals helps homogenize the inflow-velocity profile and thus is critically important for enhanced oil recovery. This paper derives a coupled reservoir/wellbore flow model that is based on inflow-velocity-control theory. Genetic algorithms are applied to solve the model because they excel in obtaining the global optimal on discrete functions. The optimized perforating strategy applies a low perforation density in high-permeability intervals and high perforation density in low-permeability intervals. As a result, the inflow-velocity profile is homogenized and idealized.