The prediction of production performance in naturally fractured reservoirs is dependent on reinfiltration and capillary continuity phenomena. In fractured reservoirs, reinfiltration and capillary continuity phenomena have been the major setback during gas-oil gravity drainage. The oil contained within the matrix of the gas invaded zone begins to drain down into the fracture system and into the lower matrix blocks, due to the force of gravity. Some of the oil that is drained out of the upper matrix blocks can reinfiltrate into the lower matrix blocks from the top or side surfaces and can flow down through the areas of contact between blocks. To evaluate the effect of reinfiltration in gravity drainage mechanism and fractured reservoir parameters: fracture width (b_f) and storativity capacity (ω) on reinfiltration process, a fractured porous media was modeled with ECLIPSE-100 Simulator. The base-case simulation runs (SIM-1 and SIM-2) showed that 55.14% and 53.40% of the oil in-place in the modeled fractured porous media were recovered by gas-oil gravity drainage mechanism without reinfiltration and with reinfiltration, respectively. Furthermore, the sensitivity study of the aforementioned fractured reservoir properties on gas-oil gravity drainage and reinfiltration with simulation runs (SIM-3 through SIM-10) indicate that fracture porosity as well as storativity capacity influence the ultimate oil recovery in naturally fractured reservoirs. Additionally, the fracture width has no influence on gas-oil gravity drainage and reinfiltration in the modeled fractured reservoir. Therefore, gravity drainage recovery mechanism proliferation is affected by oil reinfiltration within the matrix blocks that resulted in 3.173% production reduction. Hence, fracture porosity and storativity capacity are considerable factors in reinfiltration mechanism in naturally fractured reservoirs. Keywords Gravity drainage, Reinfiltration, Oil recovery, Fracture width, Fracture porosity, Storativity capacity, Naturally fractured reservoirs
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