The relationship between perforation orientation determined by near well coupling in oil reservoirs and oilfield development

In order to achieve accurate simulation of different perforation orientations during reservoir numerical simulation for horizontal wells, and to improve the simulation accuracy in the well and near-well regions, as well as to investigate the influence of various perforation orientations in horizontal wells on reservoir development, a detailed reservoir-near well-well coupling model was established using three types of grids: corner-point grids, layered unstructured grids and three-dimensional radial grids. This model enables a detailed description of radial flow near the well and the spatial distribution of perforation orientations. By using this model, the influences of four perforating patterns, including top, middle, bottom and all perforations, on reservoir development under two different well diameter conditions were studied. The simulation results show that the top perforation pattern covers the largest affected area, with the lowest bottomhole pressure, the highest cumulative oil production and the best production behavior. The middle and all perforation patterns show similar production behavior, with moderate affected areas and cumulative oil production among the four perforation patterns, but higher bottomhole pressure. The bottom perforation pattern covers the smallest affected area, with lower bottomhole pressure, the lowest cumulative oil production and the worst production behavior. Therefore, the choice of perforation orientation in horizontal wells should prioritize the top perforation pattern. However, due to the lower bottomhole pressure associated with the top perforation pattern, which may lead to gas breakout, the middle or all perforation patterns should be considered if gas breakout is a concern, and bottom perforation pattern is not recommended.