Oil Recovery Mechanism of Polymer Gel Injection Between Injection Wells and Production Wells to Block the Dominant Channel of Water Flow

Gel system profile control and flooding is a novel profile control technology designed to address the issue of inefficient and ineffective water circulation in high water cut reservoirs during their later stages, demonstrating significant development potential. This system expands on the swept volume and enhances oil displacement efficiency, ultimately improving oil recovery. In this study, a new "injection well + intermediate well" configuration was employed to conduct physical simulation experiments on core modules using the gel system (Partially Hydrolyzed Polyacrylamide + Cr³⁺ cross-linker + Stabilizer). By adjusting the gel system dosage and the location of the intermediate well (0.123 PV + midway between the injection and production wells), changes in the recovery rate, water cut, seepage field, pressure field, oil saturation field, and swept volume were observed. The experimental results indicate that under these conditions, the model achieved the highest total recovery rate, with optimal displacement of remaining oil. Additionally, the gel system exhibited strong stability after formation and was resistant to breakthrough. Compared to single-injection well profile control and flooding, the configuration increased the recovery rate by 16.7%, demonstrating promising development prospects and application potential.