Influence of Characteristic Distance Between Wells on the Efficiency of Reserves Production in a Fractured Reservoir

Fractured reservoirs are widespread and contain a significant share of hydrocarbon reserves. At the same time, the fracturing of rocks has a significant impact on the processes of oil field development. In particular, the use of flooding of fractured reservoirs can lead to rapid water breakthroughs to production wells. In this regard, it is important to study the characteristic distance between wells (well grid density) on the efficiency of reserve development in a fractured reservoir. The paper considers two-dimensional two-phase fluid flow of incompressible fluids in a fractured-porous reservoir. The study was carried out using the example of three variants of fracture systems with the same density, characterized by different degrees of connectivity. These fracture systems were obtained by random generation, with each fracture having a random position and orientation. The distribution of fracture length follows a power law. Simulation of fluid flow in a fractured-porous medium was carried out using a discrete fracture model. The influence of the characteristic distance between wells on the efficiency of reserve development was studied.

The study of equivalent permeability and oil recovery factor on the characteristic distance between wells showed that in a fractured reservoir, the placement of production and injection wells at small distances from each other, depending on the structure of the fracture system, can be either ineffective or associated with an increased risk.

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